Name: Parmesan and Broccoli Casserole Recipe
Cook time: 1 h 45 min
Yield: 8 servings
Ingredients: 6 ounces finely grated Parmesan cheese , grated on the small holes of a box grater (about 2 1/2 cups); 1/2 cup water; 20 ounces broccoli crowns , cut into 1-inch florets; 8 tablespoons unsalted butter (1 stick), plus more as needed; 1 medium yellow onion , small dice; 1/2 cup all-purpose flour; 1 1/2 teaspoons kosher salt , plus more as needed; 1/4 teaspoon freshly ground black pepper , plus more as needed; 5 cups whole milk; 6 large egg yolks , at room temperature; 6 large egg whites , at room temperature; 1/4 teaspoon cream of tartar

Why it works: Broccoli and onion match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 3,294 recipes. Both carry coumarin, which smells sweet, hay. 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.

Broccoli + oniontop 6% of all pairs

Smell alikestrong

Cooked together3,294 recipes

Shared aroma: coumarin (sweet, hay).
Butter + milktop 7% of all pairs

Smell alikemoderate

Cooked together81,283 recipes

Shared aroma: (z)-4-heptenal (biscuit, cream).
Parmesan cheese + buttertop 9% of all pairs

Smell alikemoderate

Cooked together4,163 recipes

Shared aroma: guaiacol (smoky, sweet).
Broccoli + peppertop 9% of all pairs

Smell alikemoderate

Cooked together2,747 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Onion + peppertop 11% of all pairs

Smell alikemoderate

Cooked together68,474 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).

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

Swap the onion

How well each one fits the dish's main ingredients (parmesan cheese, broccoli, butter, flour, pepper, milk, egg):

Asparagusfits better
Spinachfits better
Chivefits better
Onionthe original

Fit is the average pairing score against parmesan cheese, broccoli, butter, flour, pepper, milk, egg. Candidates are from the same food group and used in at least 100 recipes.

Ingredient	Portion assumed	kcal
Flour	1 cup (125g) all-purpose	455
Milk	1 cup (244ml) whole	149
Parmesan Cheese	1 oz (28g)	110
Butter	1 tbsp (14g)	102
Egg	1 large egg (50g)	78
Broccoli	1 cup chopped (156g)	55
Cream	1 tbsp (15ml) heavy	51
Onion	1 medium (110g)	44
Black Pepper	1 tsp ground (2.3g)	6
Salt	1 tsp (6g)	0
Water	not in our table	0

Parmesan and Broccoli Casserole Recipe