Broccoli soup

The stalks are the soup

Many recipes throw the stalk away, which is both wasteful and a mistake. The stalk is sweeter than the florets and has a denser, less sulfurous flavor. Peeled and sliced thin, it cooks down into the body of the soup. The florets are added at the end for color and freshness, not for substance.

The reason for the four-minute rule on the florets is the same as with any brassica: sulfur compounds break down with prolonged heat into the smell people associate with overcooked cabbage. Four minutes is enough to soften them and not enough to start that reaction.

Why there is a potato in it

One potato is doing structural work rather than flavor work. Blended, its starch gives the soup a body that broccoli alone cannot — the alternative is cream, which costs considerably more calories for a similar effect. If you want it richer anyway, a splash of cream at the end is fine; you will not need the potato as well.

The cheese question

Broccoli and cheddar is a classic pairing for good reason, and it adds about 70 percent to the calories. Around 30 g of sharp cheddar per serving adds about 120 kcal and 7 g of protein. Using a strongly flavored cheese means you need less of it — a sharp aged cheddar at 20 g delivers more flavor than a mild one at 40 g.

Keeping it

Four days refrigerated. It freezes acceptably but the texture loosens slightly; blending again after thawing fixes it. The color dulls in storage regardless, which is cosmetic.

What it is worth nutritionally

Broccoli is among the better vegetable sources of vitamin C and vitamin K, and it carries glucoraphanin, which the body turns into sulforaphane — the compound behind most of the interest in cruciferous vegetables. Glucoraphanin itself survives cooking fairly well, but myrosinase, the enzyme that converts it, is destroyed by long heat, which is another argument for the short cooking time here.