Name: Baked Fish Portuguese-style
Ingredients: 2 large onions, chopped; 2 stalks celery, chopped; 2 tomatoes, chopped; 1/4 of a cup of butter; 1/2 of a cup of tomato juice; 2 tbsp. lemon juice; 3 or 4 cloves garlic, crushed; 1 bay leaf; Salt & pepper to taste; 1 to2 lbs. fish fillets of your choice

Why it works: Lemon and pepper match in chemistry and in kitchens. They rank in the top 3% of all ingredient pairs, and cooks put them together in 27,047 recipes. Both carry trans-2-nonenal, which smells cardboard, fatty. The science ↓

Explore the science

The flavor team

The pairs that carry this dish. Each one is judged two ways: how much their aromas overlap, and how often cooks already put them together.

Lemon + peppertop 3% of all pairs

Smell alikestrong

Cooked together27,047 recipes

Shared aroma: trans-2-nonenal (cardboard, fatty).
Celery + lemontop 3% of all pairs

Smell alikestrong

Cooked together3,467 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Celery + tomatotop 4% of all pairs

Smell alikemoderate

Cooked together3,377 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Clove + peppertop 5% of all pairs

Smell alikestrong

Cooked together17,451 recipes

Shared aroma: ethyl octanoate (fruity, wine).
Celery + peppertop 5% of all pairs

Smell alikestrong

Cooked together16,012 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

What each ingredient does

Fish fillets: Form the main protein that cooks through and turns opaque in the oven.
Onions: Soften and turn sweet as they cook, forming the base of the sauce.
Tomatoes: Break down into the sauce, adding moisture, acidity and body.
Butter: Adds fat and richness and carries flavor when the vegetables are sautéed.
Celery: Adds savory aroma and a mild crunch that softens into the sauce.
Garlic: Adds pungent aroma that mellows as it cooks in the sauce.

The step that matters

Cook the sauce until the vegetables are tender. Sautéing the onions, celery and tomatoes fully softens them and drives off excess water, so the sauce becomes concentrated rather than thin and watery when poured over the fish.

Swap the onion

How well each one fits the dish's main ingredients (celery, tomato, butter, lemon, clove, pepper, fish):

Capsicumfits better
Carrotfits better
Spinachfits better
Onionthe original

Fit is the average pairing score against celery, tomato, butter, lemon, clove, pepper, fish. Candidates are from the same food group and used in at least 100 recipes.

“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.

Ingredient	Portion assumed	kcal
Salmon	100g cooked	208
Butter	1 tbsp (14g)	102
Onion	1 medium (110g)	44
Tomato	1 medium (123g)	22
Lemon	juice of 1 lemon (48ml)	12
Celery	1 stalk (40g)	6
Black Pepper	1 tsp ground (2.3g)	6
Garlic	1 clove (3g)	4
Bay Leaf	1 leaf (0.6g)	2
Salt	1 tsp (6g)	0

Baked Fish Portuguese-style