Prep cook screening questions: prep lists, knife work, date marking, thawing and slicer rules
On this page
Prep cook screening questions should find out whether the candidate can work through a prep list on their own, at a steady pace, with consistent knife cuts and good yield, and whether their food safety habits hold up when no one is watching: labeling and date marking, thawing safely, cooling, and keeping raw and ready-to-eat food apart. Then confirm the early-morning schedule, the food handler card rule for the job's state, and that the candidate is 18 or older if the job includes the slicer or a commercial mixer. A short paid prep test is the best final check.
This page stays with prep: the person who gets the kitchen ready before service. For cooks on the line during service, use line cook screening questions, which also covers food handler card rules in California, Texas and Illinois and the holding and cooling temperatures. For entry-level dish and kitchen porter roles, see dishwasher screening questions. A matching job ad is in the prep cook job description template.
Which prep kitchen is it?
| Kitchen | What changes for prep | Ask the candidate |
|---|---|---|
| Scratch restaurant | Stocks, sauces, butchery, many small items, a prep list from the chef each morning | "What did you make from raw ingredients on a normal morning?" |
| Commissary or central kitchen | Large batches for several locations, recipes by weight, packaging and labels, production targets | "How big were your batches, and how did you scale a recipe?" |
| Hotel or banquet | Volume for events, cold platters, early starts, changing menus | "What was the biggest event you prepped for?" |
| Institutional (school, hospital, senior living) | Standardized recipes, special diets and textures, strict documentation | "Have you prepped texture-modified or allergen-free meals?" |
| Grocery deli or prepared foods | Slicing, salads, rotisserie, retail labels | "Did you run the slicer, and how did you clean it?" |
Rules that shape a prep cook screen
As of October 2026, not legal advice. Food codes are adopted by states and localities, and youth employment rules can be stricter under state law. Confirm the rules for the kitchen's location.
Age and powered equipment
The Department of Labor's Hazardous Occupations Order 10, 29 CFR 570.61, bars workers under 18 from operating, feeding, setting up, adjusting, repairing or cleaning power-driven meat slicers, grinders, choppers and similar machines, and it says so "regardless of the product being processed", with slicing vegetables, bread and cheese in a deli as examples. The DOL's restaurant fact sheet applies the same limit to commercial mixers and certain bakery machines, and bars 14- and 15-year-olds from baking and from power-driven food slicers, grinders, processors and mixers. If the prep job includes those machines, "Are you at least 18?" is a lawful, job-related question. Do not ask for a date of birth.
Food handler cards
The FDA Food Code is a model that states adopt, so card rules vary. Two examples not covered on the line cook page:
| State | Rule as the state describes it | Source |
|---|---|---|
| Washington | Food workers need a Washington food worker card. A new worker can work up to 14 days before getting it if the employer provides food safety training. The first card is valid for two years; cards from other states are not accepted. | Washington State Department of Health |
| Oregon | Food service workers get a food handler card within 30 days of beginning work. It costs $10, is valid for three years, and cards from other states are not valid in Oregon. | Oregon Health Authority |
Knockout questions
| Question | What a strong answer sounds like | Red flags |
|---|---|---|
| Prep starts at [time], [days], including weekends before big services. Can you be here on time every shift? | Yes, with a plan for an early start. | Unsure how they would get in before transit starts. |
| This location requires [food handler card] within [period]. Do you have one, and when does it expire? | Names the card and date, or will get it in the first week. | An out-of-state card presented as valid where it is not. |
| (If the job uses the slicer or mixer) Are you at least 18? | Yes. | Hesitation. Ask only about the minimum. |
| The job means standing for the full shift, lifting cases of produce and stock pots, and working in the walk-in. Can you do that, with or without reasonable accommodation? | Yes. | None from the answer. No medical follow-ups. |
| Can you do a paid prep test on [dates]? | Yes, with a date. | Unavailable for any trial before the start date. |
Prep list, par and pace questions
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"You walk in at 6 a.m. and the chef left a prep list with fifteen items. How do you decide what to do first?"
- Strong answer: checks what is already on hand against the pars, starts anything with a long cook or cooling time (stocks, braises, doughs), then items needed first at service, then quick cold items last, and tells the chef early if something is missing.
- Red flags: "Top to bottom," with no thought for cook or cooling times.
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"What is a par, and what did you do when you were short of one at the end of prep?"
- Strong answer: the amount of each item the kitchen needs on hand for service; counts, preps to par, and tells the chef or lead what will be short and why.
- Red flags: has worked prep and has not heard the word.
-
"How long does a 50-pound case of onions take you to dice, and what size dice?"
- Strong answer: an honest time for a stated cut, and what changes it (peeling, a dull knife, a robot coupe for some cuts).
- Red flags: a time that does not survive the follow-up question about how many onions are in the case.
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"How do you get good yield when you break down whole proteins or produce?"
- Strong answer: specific: trims close, saves usable trim for stock or staff meal, portions by weight, tells the chef when a case comes in with poor quality.
- Red flags: throws away anything that is not perfect, or never weighs.
Checking a speed claim (invented example)
A candidate says they can dice a 50-pound case of onions in 30 minutes. A case of that size might hold roughly 100 medium onions, so that is about one onion every 18 seconds, peeled and diced by hand. Fast cooks can approach that for a large dice; it is unlikely for a fine dice. Ask them to describe one onion, step by step. You are finding out whether the number is theirs.
Food safety questions for prep
These answers follow the FDA Food Code 2022, which many local codes follow. Accept a candidate's local numbers if they can explain them.
| Question | Answer in line with the Food Code | Red flags |
|---|---|---|
| How do you label something you prepped today that will be used over the next few days? | Item name and a use-by date. Under section 3-501.17, ready-to-eat, time/temperature control for safety food held more than 24 hours is date marked and kept at 41°F (5°C) or below for up to 7 days, with the day of preparation counted as day 1. | "I just write the day I made it," with no idea of the limit. |
| How do you thaw a case of frozen chicken? | In the walk-in, or under cold running water (70°F or below) in a way that keeps it safe, or as part of cooking (section 3-501.13). | On the counter overnight, or in a sink of standing water. |
| How do you handle lettuce you have cut, sliced tomatoes or cut melon? | Treats them as needing temperature control: cut leafy greens, cut tomatoes and cut melons are time/temperature control for safety foods under the Food Code, so they go straight into the cooler, labeled. | Leaves cut melon at room temperature until service. |
| When can you touch ready-to-eat food with bare hands? | Generally not. Section 3-301.11 calls for utensils, deli tissue or single-use gloves for ready-to-eat food, with narrow exceptions such as food that will be cooked afterwards. | Builds salads bare-handed after handling raw meat. |
| How do you organize the walk-in after a delivery? | First in, first out: new product behind old, ready-to-eat above raw, raw proteins below by cooking temperature, everything labeled. | Puts new cases in front. |
Do not ask about health or illness before an offer. You can say: "The kitchen requires employees to follow its illness reporting policy. Can you follow that?"
Equipment and cleaning questions
- "Which equipment have you used on your own?" Listen for specifics: slicer, food processor, buffalo chopper, mixer, immersion blender, combi oven, tilt skillet, vacuum sealer. Ask who trained them on each.
- "Walk me through cleaning the slicer." Strong: unplugs it, sets the blade to zero, uses a cut-resistant glove, takes it apart in order, washes, rinses, sanitizes, air dries, reassembles. Red flag: wipes it down while plugged in.
- "How do you keep your station clean during prep?" Strong: cleans as they go, separate boards for raw protein and produce, sanitizer bucket at the right strength, trash and compost managed. Red flag: cleans "at the end".
- "What do you do when you cut yourself?" Strong: stops, washes and bandages with a glove over it, discards any food that may be contaminated, tells the lead. Red flag: keeps working.
The paid prep test
Thirty to sixty minutes on real items beats any question. Give the candidate a short prep list from the menu, for example one onion diced, one case of a vegetable broken down, a protein portioned to a stated weight and a sauce from a recipe card, and watch knife grip and safety, consistency of cuts, speed, yield, cleaning as they go, and whether they label and date everything without being reminded. Treat the time as paid work; details are in how to run a job trial day.
How prep experience gets overstated
- Assembly as scratch prep. Opening bags of pre-cut vegetables is not breaking down cases. Ask what they cut from whole.
- "Butchery" that was portioning pre-cut steaks. Ask what came in whole.
- Equipment by proximity. "Used the slicer" because it was in the kitchen. Ask how they cleaned it.
- Batch size inflated. A commissary's total output quoted as their own. Ask what they made on their last shift.
Scoring the screen
Pass or fail: can work the early schedule; meets the food handler rule on time; 18 or older if the role uses the slicer or mixer; can do the job with or without accommodation; available for a paid prep test.
Scored 0 to 2 each (10 possible):
- Prep planning: works a list by cook and cooling time.
- Knife work and yield: named cuts, honest speed, saves usable trim.
- Date marking and storage: labels, FIFO, 7-day limit or the local rule.
- Thawing and cut produce handled safely.
- Cleaning and equipment: safe slicer cleaning, clean as you go.
Legal cautions
Ask about availability, not childcare or religion, and about age only as a legal minimum for the equipment. Keep medical questions out of the screen. Criminal history questions are restricted in many places; see ban-the-box interview questions, and the full list is in illegal interview questions. This page is general information, not legal advice.
Questions people ask
Can a 16-year-old prep cook use a meat slicer?
No. Under the Department of Labor's Hazardous Occupations Order 10 (29 CFR 570.61), workers under 18 may not operate, feed, set up, adjust, repair or clean power-driven meat slicers, and the rule applies whatever is being sliced, including vegetables, bread and cheese. The DOL's restaurant fact sheet applies the same limit to commercial mixers and certain bakery machines (as of October 2026).
How long can prepped food be kept in the walk-in?
Under the FDA Food Code 2022 (section 3-501.17), ready-to-eat, time/temperature control for safety food prepared in the kitchen and held more than 24 hours must be marked with a use-by date and can be held at 41°F or below for up to 7 days, counting the day of preparation as day 1. Your state or local food code is the rule that applies, so confirm it with the health department.
Does a prep cook need a food handler card?
It depends on the state and sometimes the county. For example, Washington requires a state food worker card, with up to 14 days to get it if the employer provides food safety training first, and does not accept other states' cards. Oregon requires a food handler card within 30 days of starting work, valid for three years. Check the health department for the job's location.
What is a good practical test for a prep cook?
A short paid trial with real tasks from the prep list: dice an onion, break down a case of one vegetable, portion a protein to a spec, label and date everything. Watch knife safety, speed, consistency of cuts, how they clean as they go, and whether they label without being reminded.