Menu Costing Under Protein Price Volatility
You are the chef de cuisine of a 120-seat bistro. Your top-selling dish is a pan-roasted chicken breast with seasonal vegetables, priced at $28. The plate cost was $8.50 (30.4% food cost) when chicken breast was $5.50/kg. Your purveyor now quotes $7.80/kg, an increase of 42%. The dish sells 80 covers per week. Your target food cost is 30%. You have a 4-week window before the next menu change. You cannot raise the menu price without triggering a customer backlash, and your owner has mandated that overall food cost must remain at or below 30%.
1. Calculate the new plate cost and food cost percentage for the chicken dish if you change nothing. Show your work. Then determine the maximum allowable plate cost to maintain 30% food cost at the current menu price.
Read the worked answer
Original plate cost = $8.50, of which chicken cost = 6 oz (170 g) × $5.50/kg = $0.935. Wait, that seems low. Let's recalculate: 170 g = 0.17 kg × $5.50/kg = $0.935. But the total plate cost is $8.50, so chicken is only 11% of plate cost? That can't be right-chicken breast at $5.50/kg is $2.50/lb, which is plausible. But if the plate cost is $8.50, the chicken portion must be larger or there are other expensive ingredients. Let's assume the chicken portion is 8 oz (227 g). Then chicken cost = 0.227 kg × $5.50 = $1.25. Still not $8.50. Perhaps the $8.50 includes sides and garnish that are costly. For the purpose of this exercise, we need to isolate the chicken cost. The problem states the plate cost was $8.50 when chicken was $5.50/kg. We are not given the chicken portion size. To find the new plate cost, we need the chicken cost per plate at the old price. Without portion size, we cannot compute exactly. However, we can express the increase: if chicken cost was C dollars per plate at $5.50/kg, then at $7.80/kg it becomes C × (7.80/5.50) = 1.418C. The increase in plate cost is 0.418C. The new plate cost = $8.50 + 0.418C. To maintain 30% food cost at $28, maximum plate cost = 0.30 × $28 = $8.40. Since the original plate cost was $8.50, which is already above $8.40, the dish was already over target. So the new plate cost will be even higher, and you must reduce costs elsewhere or change the dish. The key insight: you cannot maintain 30% with this dish at $28 unless you reduce the chicken portion or substitute ingredients. A model answer should note that the original food cost was 8.50/28 = 30.36%, slightly over target. Any increase makes it worse. The maximum allowable plate cost is $8.40. Therefore, you need to reduce plate cost by at least $0.10 plus the increase. If chicken is, say, $2.00 of the $8.50, then new chicken cost = $2.00 × 1.418 = $2.84, increase $0.84, new plate cost $9.34, food cost 33.4%. To get back to 30%, you need to cut $0.94 from the plate. Options: reduce chicken portion from 8 oz to 7 oz (saves $0.31), use chicken thigh (cheaper), adjust sides, etc. The model answer should demonstrate the calculation with an assumed chicken cost or show the algebraic relationship and conclude that the dish cannot remain at $28 with 30% food cost without significant changes.
2. Propose two specific operational changes to the dish that would reduce the plate cost back to $8.40 or below without raising the menu price, and explain the impact on perceived value and kitchen execution.
Read the worked answer
- Reduce the chicken portion from 8 oz to 7 oz and add a more filling starch (e.g., increase potato purée by 1 oz). This reduces chicken cost by 12.5% (from $2.84 to $2.49, saving $0.35) and adds minimal cost for starch (about $0.10), net savings $0.25. Perceived value: customers may not notice a 1 oz reduction if the plate looks full; the added starch maintains plate volume. Kitchen execution: simpler, as starch is batch-prepared. 2. Switch from chicken breast to chicken thigh, which is typically 30-40% cheaper. If thigh is $4.80/kg, cost for 8 oz = $1.09 vs $2.84 for breast, saving $1.75. Perceived value: thigh is juicier and more flavorful, but some customers perceive it as lower quality. You could rebrand the dish as 'braised chicken thigh' with a rich sauce. Kitchen execution: thighs require different cooking method (braise vs roast), but can be cooked in bulk and held. Either change brings plate cost below $8.40. The model answer should include calculations and consider customer perception and operational feasibility.