Name: Three-onion Asparagus Soup
Ingredients: 2 TBS. BUTTER; 1 large leek, white part only, well washed and chopped; 4 scallions, trimmed and chopped; 1/2 lb. potatoes (1 large), peeled and cubed; 1 lb. asparagus, trimmed and chopped; 4 cups vegetable stock; Salt to taste; About 1 Tbs. lemon juice; 1/3 cup crème fraîche, sour cream or plain yogurt; 12 to 16 chives, sliced; 4 radishes, thinly sliced

Why it works: Leek and chive share more aroma than cooks usually use. They rank in the top 1% of all ingredient pairs, and cooks put them together in 29 recipes. Both carry 1-octen-3-ol, which smells mushroom, earthy. 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.

Leek + chivetop 1% of all pairs

Smell alikestrong

Cooked together29 recipes

Shared aroma: 1-octen-3-ol (mushroom, earthy).
Leek + asparagustop 1% of all pairs

Smell alikestrong

Cooked together73 recipes

Shared aroma: 1-octen-3-ol (mushroom, earthy).
Asparagus + chivetop 2% of all pairs

Smell alikestrong

Cooked together165 recipes

Shared aroma: guaiacol (smoky, sweet).
Chive + radishtop 2% of all pairs

Smell alikestrong

Cooked together30 recipes

Shared aroma: coumarin (sweet, hay).
Potato + chivetop 2% of all pairs

Smell alikemoderate

Cooked together611 recipes

Shared aroma: decanal (soap, orange peel).

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

What each ingredient does

Leek and scallions: Soften slowly in butter to build a sweet, mellow base for the soup.
Potatoes: Break down during simmering and puréeing to give the soup a thick, creamy body.
Asparagus: Provides the main vegetable flavour and, with the potatoes, contributes to the soup's texture.
Vegetable stock: Liquid that cooks the vegetables and sets the soup's overall volume and savoury flavour.
Crème fraîche, sour cream or plain yogurt: Adds cool richness and a tangy acidity that balances the soup's earthy vegetable flavour.
Lemon juice: Adds acidity that brightens the flavour of the soup.

The step that matters

Purée until very smooth. Cooked potato and asparagus fibres only turn silky when blended thoroughly. Stopping early leaves a gritty or stringy texture, and blending in batches prevents the hot liquid from splattering or straining the machine.

Swap the lemon

How well each one fits the dish's main ingredients (butter, leek, potato, asparagus, cream, chive, radish):

Avocadofits about as well
Lemonthe original
Limefits less well
Coconutfits less well

Fit is the average pairing score against butter, leek, potato, asparagus, cream, chive, radish. 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
Potato	1 medium (173g) baked	161
Butter	1 tbsp (14g)	102
Yogurt	170g plain Greek	100
Onion	1 medium (110g)	44
Asparagus	6 spears (90g)	27
Lemon	juice of 1 lemon (48ml)	12
Chive	1 tbsp (3g)	1
Salt	1 tsp (6g)	0

Three-onion Asparagus Soup