The Potato Paradox

It is the cheapest ingredient in your kitchen. A sack of dirty whites costs peanuts compared to the beef. Yet, the humble roast potato causes more arguments in commercial kitchens than anything else.

Why? Because of the “Fear of the Empty Tray.”

Chefs are terrified of running out of roasties. So they over-peel. They over-prep. They fill the ovens with tray after tray. And at 5:00 PM, you end up throwing 10kg of roasted, wrinkly, unsold potatoes in the bin.

You didn’t just throw away potatoes. You threw away the labor hours it took to peel them, the gas it took to par-boil them, and the oil/fat used to roast them. Getting the “Potatoes Per Person” ratio right is the easiest way to stop burning cash in the kitchen.

The Philosophy: The “Carb Shield”

Rory Sutherland would tell you that the potato is not just food; it is a Distraction Technique.

If a plate looks empty, the customer stares at the meat. They analyse the size of the beef slice. They calculate value. If the plate is piled high with golden, crispy roast potatoes, the brain registers “Abundance.”

The potato is your “Carb Shield.” It protects your margin. It allows you to serve a strict 150g portion of beef (expensive) without the customer feeling short-changed, because the plate is physically heavy with potatoes (cheap). Generosity with the potato allows you to be strict with the protein.

The Tactics: The Golden Ratios

Stop guessing. Stop letting the Commis Chef “eyeball” the sacks. Here is the catering math for commercial success.

1. The Magic Number is 3 (But big ones) Psychologically, “Three” is a satisfying number. Two looks stingy. Four looks messy.

• The Rule: Aim for 3 large roast potatoes per plated cover.
• The Weight: This equates to roughly 200g-220g of RAW potato per person.
• The Math: If you have 100 bookings, you need 22kg of raw peeled potatoes. Not 30kg. Not “about two sacks.” 22kg.

2. The “Buffet Buffer” (The Carvery Factor) If you are running a self-serve carvery or buffet, the rules change. The “Greed Factor” kicks in. When people serve themselves, they take 20% more than they can eat.

• The Rule: Increase allowance to 300g raw weight per person.
• The Tactic: Cut them larger. A massive potato takes up more tray space and plate space. A customer will take two giant potatoes, but they might take six small ones. Two giant ones weigh less than six small ones. Control the size to control the take.

3. The “Peel Loss” Trap You buy a 25kg sack. You think you have 25kg of potatoes. You don’t. After peeling and removing eyes/bruises, you lose about 15-20% of the weight.

• The Calculation: If you need 20kg of cooking weight, you need to buy 25kg of dirty weight.
• If you don’t factor this in, you will run out.

4. The Par-Boil Production Line Don’t roast from raw. It takes too long and the shrinkage is worse.

• The Tactic: Par-boil until the edges break up (fluffy edges = crispier roasties). Blast chill them.
• You can prep 100% of your Sunday potatoes on Saturday. On Sunday, you are just “finishing” them in hot fat. This saves oven space and labor during the busy service.

The Software Pitch: The Prep List Automator

Calculating “220g x 145 bookings + 15% peel loss” at 9:00 AM while the phone is ringing is a recipe for disaster. You will get it wrong. You will either run out (disaster) or over-prep (waste).

You need the Roast Forecaster.

This tool doesn’t just do costs; it does Quantities.

• Input your booked covers (e.g., 145).
• It tells you: “You need exactly 34kg of raw potatoes from the sack.”
• It tells you: “This will yield approx 450 roast potatoes.”

It generates your Prep List for you. You hand the iPad to the Commis Chef and say: “The software says peel 34kg. Not 33kg. Not 35kg. 34kg.”

It creates accountability. It stops the waste.

👉 Get the tool here: https://smartpubtools.com/sunday-roast-forecaster/

The Conclusion

The potato is the workhorse of the Sunday Roast. It is your best friend for margin protection. But only if you treat it with respect. Measure the raw weight. Control the portion. And use the potato to make the customer feel full, so your bank balance stays full too.