Proper portion control on seasonal dishes can save you 15-20% on food costs within the first month. Asparagus costs €12 per kilo in May, then jumps to €18 by August. Your chef doesn't track these price swings and keeps serving the same generous portions, watching your margins disappear.
Why seasonal dishes are different
Fixed menu items? You know their food cost by heart. But seasonal products shift price every single week. White asparagus costs €12 per kilo today, €18 next week. Your chef doesn't realize this and plates the same generous portions.
The result: food cost jumps from 28% to 45% overnight.
Set fixed portion guidelines for each seasonal dish
For every seasonal dish, you decide upfront:
- Main product: Exact grams per portion (example: 400g asparagus)
- Garnish: Precise amount (example: 50g hollandaise, 2 ham slices)
- Side dishes: Fixed portions (example: 3 baby potatoes, 10g parsley)
💡 Example: Asparagus dish
Fixed portion guideline:
- White asparagus: 400g per portion
- Hollandaise sauce: 50ml
- Cooked ham: 2 slices (60g)
- Cooked baby potatoes: 3 pieces (150g)
- Parsley: pinch (5g)
This guideline applies always, regardless of asparagus purchase price.
Calculate your maximum purchase price
Once you know your spending, work backwards to find what you can pay maximum for the seasonal product.
Formula:
Maximum purchase price per kg = (Desired food cost × Selling price excl. VAT - Other ingredients) ÷ Main product in kg
💡 Example: Maximum asparagus price
Asparagus dish sells for €28.50 incl. VAT (= €26.15 excl.)
Desired food cost: 32%
- Total ingredient budget: €26.15 × 0.32 = €8.37
- Other ingredients: €3.20 (sauce, ham, potatoes)
- Budget for asparagus: €8.37 - €3.20 = €5.17
- For 400g = €5.17 ÷ 0.4kg = €12.93 per kg maximum
Make your guidelines visible in the kitchen
The smartest guideline fails if nobody sees it. Visual cues work better than verbal instructions. Post a card next to each seasonal dish with:
- Photo of the plated dish
- Exact portion sizes in grams/ml
- Current purchase price and date
- Warning if price gets too high
⚠️ Note:
Update your cards weekly. Seasonal prices change fast and your staff needs to know when they should be more careful with portions.
Use a scale and measuring cups
"A good splash of sauce" means 30ml to one cook and 80ml to another. That difference costs you €2 per plate.
Make sure you have:
- Digital scale at every mise-en-place station
- Measuring cups for sauces (25ml, 50ml, 100ml)
- Standard serving spoons for side dishes
- Portion ice cream scoops for purees and mousses
Monitor your food cost weekly
With seasonal dishes, check weekly if you're still within margin. Calculate:
- How many portions you sold this week
- What were the actual purchase prices
- What was your average food cost
💡 Example: Weekly check
Week 1: Asparagus €11/kg → Food cost 29%
Week 2: Asparagus €15/kg → Food cost 35%
Action week 3: Raise price to €31.50 or reduce portion to 350g.
Plan your exit strategy
Every seasonal dish has a point where it becomes too expensive. Determine upfront:
- At what purchase price you stop offering the dish
- Which dish you put back on the menu instead
- How you communicate this to guests
From years of working in professional kitchens, I've seen restaurants lose thousands by clinging to seasonal specials that stopped making sense financially. A food cost calculator helps you make these calculations automatically and track your food cost per dish, even if prices change daily.
How do you set portion guidelines? (step by step)
Determine your ideal portion size
Weigh all components of your seasonal dish and note the exact quantities. Test the dish with different portion sizes to find the right balance between taste and cost.
Calculate your maximum purchase price
Work backwards from your desired food cost to figure out what you can pay at most for the main ingredient. Use the formula: (Food cost × Selling price excl. VAT - Other costs) ÷ Quantity of main product.
Create clear instruction cards
Post a card at each workstation with a photo of the dish, exact portion sizes, and current prices. Update these weekly and train your staff to follow the guidelines.
✨ Pro tip
Weigh your 3 most profitable seasonal dishes every Wednesday for 6 weeks. If individual portions vary by more than 25g between cooks, your guidelines need clearer visual references and stricter enforcement.
Calculate this yourself?
In the KitchenNmbrs app you can do this in just a few clicks. 7 days free, no credit card.
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Frequently asked questions
How often should I adjust my portion guidelines?
Check your purchase prices and food cost weekly. Adjust your guidelines if your food cost exceeds your desired percentage or if the quality of the seasonal product declines. Most restaurants find weekly monitoring catches problems before they spiral out of control.
What if my chef says smaller portions hurt quality?
Explain that consistent portions actually guarantee quality. A guest who got 500g of asparagus last week and 300g this week will notice the difference immediately. Fixed portions ensure a predictable experience every single time.
Should I calculate different maximum prices for peak vs off-peak seasons?
Absolutely, but set them before the season starts. Peak season asparagus might justify €18/kg if you're charging premium prices, while early season could max out at €12/kg. Having predetermined price points prevents emotional decision-making during busy periods.
📚 Sources consulted
- EU Verordening 852/2004 — Levensmiddelenhygiëne (2004) — Official source
- EU Verordening 853/2004 — Hygiënevoorschriften voor levensmiddelen van dierlijke oorsprong (2004) — Official source
- EU Verordening 1169/2011 — Voedselinformatie aan consumenten (2011) — Official source
- NVWA — Hygiënecode voor de horeca (2024) — Official source
- NVWA — Allergenen in voedsel (2024) — Official source
- Codex Alimentarius — International Food Standards (2024) — Official source
- FSA — Safer food, better business (HACCP) (2024) — Official source
- BVL — Lebensmittelhygiene (HACCP) (2024) — Official source
- Warenwetbesluit Bereiding en behandeling van levensmiddelen (2024) — Official source
- WHO — Foodborne diseases estimates (2024) — Official source
Food Standards Agency (FSA) — https://www.food.gov.uk
The HACCP standards shown in this application are for informational purposes only. KitchenNmbrs does not guarantee that displayed values are current or complete. Always consult the FSA or your local authority for the latest regulations.
Written by
Jeffrey Smit
Founder & CEO of KitchenNmbrs
Jeffrey Smit built KitchenNmbrs from 8 years of hands-on experience as kitchen manager at 1NUL8 Group in Rotterdam. His mission: give every restaurant owner control over food cost.
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