How do you work out the cost of a dish?
Take one portion, as it actually leaves the kitchen, and write down every ingredient in it with the amount used. Then price each amount at what you paid for it, not at the shelf price and not at what you paid last year. Add them up. That total is what that plate cost you in ingredients.
A worked example, using round numbers rather than real ones, because your supplier prices are not ours:
| Ingredient | Amount in one portion | What that amount cost |
|---|---|---|
| Chicken | 180 g from a 2 kg pack | Pack price ÷ 2000 × 180 |
| Cooking oil | 30 ml from a 5 L jerrycan | Jerrycan price ÷ 5000 × 30 |
| Onion, tomato, spice | A handful, weighed once | Weigh it once, then reuse the figure |
| Chips | 250 g potatoes before peeling | Price the 250 g, not the 190 g that survives |
| Plate total | One portion | The number you compare to the menu price |
The row that catches people is the last one. You buy potatoes and you sell chips, and the difference between the two is a cost you paid whether or not you wrote it down. Cost the raw weight that leaves your store, not the cooked weight that reaches the plate.
Why "food cost percentage" is the number people quote
Divide the plate total by the menu price and you get a percentage. If a dish costs you 7,000 in ingredients and sells for 25,000, that is 28%.
A food cost somewhere in the high twenties to mid thirties is commonly quoted in the restaurant trade as a healthy range. Treat that as a conversation starter and nothing more. It is trade convention rather than a rule, it comes from markets with different rent, wages and supplier prices, and we have not found a Ugandan source that establishes it here. The useful comparison is not against a number from a magazine — it is against your own figure from last month.
What the percentage is genuinely good for is ranking your own menu. The dish everyone praises is not always the dish paying the rent, and until every plate is costed you cannot tell which is which.
Why the number will not sit still
A dish costed in January is not costed in June. Four things move it, and only one of them is obvious.
- Supplier prices move. Cooking oil and tomatoes can swing hard in a season. Your menu price did not move with them.
- Portions grow. Not deliberately. A busy cook serves generously, and a portion that creeps up by a tenth takes a tenth of that dish’s margin with it.
- The free extras are real. The extra sauce, the staff meal, the plate sent back and remade. Each one is ingredients that left your store and earned nothing.
- Waste is invisible until you count it. Trim, spoilage and the pot that caught. It is a cost whether or not anyone writes it down.
This is why costing a menu once, in a notebook, solves the problem for about a month. The work is not the arithmetic. The work is keeping the arithmetic true as everything underneath it moves.
How Stem handles this
Stem lets you write a recipe for a dish: which ingredients, and how much of each in one portion. When that dish is sold, the ingredients come out of stock automatically, drawn from the batch closest to expiry first, priced at what that batch actually cost you.
- Portion in the unit that makes sense. You can stock chicken in kilogrammes and portion a dish at 180 g. Stem converts between the two, so nobody has to write recipes in awkward decimals.
- Priced at the batch you actually used. If oil went up last week, the dishes cooked from the new jerrycan carry the new price and the ones before it do not.
- Dishes made ahead work too. Produce a batch of something in the morning and its ingredient cost is carried into that batch, so selling from it later prices correctly.
- Waste is recorded with a reason. You log what was thrown away and why, so spoilage stops being invisible.
Recipe tracking is off until you switch it on, because a bar selling only bottled drinks has no use for it. It is under settings, and it applies from the moment you enable it rather than backwards.
What Stem does not do is tell you what to charge. It gives you the cost honestly; the menu price is a judgement about your customers, your area and your competition, and no software should pretend otherwise.
Where to start if you have never done this
Do not cost the whole menu this week. It is the fastest way to abandon the job.
- Pick your five best-selling dishes. They are most of your revenue and most of your risk.
- Weigh each ingredient in one portion of each, on a normal service day.
- Price those amounts from your most recent supplier invoices, not from memory.
- Compare each plate total to its menu price. Expect at least one unpleasant surprise.
- Fix the worst one first — by portion size, by supplier, or by price. Then leave the rest alone until next month.
Five dishes costed honestly will teach you more about your kitchen than a full menu costed carelessly.