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The first cold Sunday night of every year, my father would come in from the porch, rub his hands together and ask if it was broccoli cheese soup weather yet. It always was, because my mother had already started it. Onion and a little carrot softened in butter, a spoon of flour stirred in to make a roux, then broth and milk whisked in slowly until the pot thickened into something smooth and creamy. The broccoli went in and simmered until it was tender enough to break with a spoon, and the kitchen windows steamed up.
Then came her rule, and she never once broke it: the pot came off the heat before the cheese went in. She grated sharp cheddar by hand and stirred it in one handful at a time, letting each melt before adding the next. Cheese that boils separates. The proteins tighten into little grains and the fat floats to the top as an oily slick. Off the heat, in a soup already thickened with a roux, it melts silky and stays that way to the last bowl. My father ate his out of a big mug, standing at the window watching the yard go dark at six o’clock.
Why this broccoli cheese soup works
- A roux base. Butter and flour thicken the soup before the cheese goes in, which keeps the cheese suspended and smooth.
- The heat goes off first. Cheese melted below a simmer never splits or turns grainy.
- A handful at a time. Small additions melt evenly instead of clumping into a ball.
- Hand-grated sharp cheddar. It melts smoothly and gives a stronger cheese taste than pre-shredded cheese.
- Some broccoli mashed in. Pressing part of the broccoli against the pot thickens the soup and spreads the flavor.
Ingredients
Makes about 8 cups, 6 generous bowls. The measurements are in US cups with grams in brackets.
For the soup
- 4 tablespoons unsalted butter (56g)
- 1 medium onion, finely chopped
- 1 medium carrot, peeled and grated or finely diced
- 2 cloves garlic, minced
- 1/3 cup all-purpose flour (40g)
- 3 cups chicken or vegetable broth (720ml)
- 2 cups whole milk (480ml)
- 1/2 cup heavy cream (120ml)
- 5 cups small broccoli florets, stems peeled and chopped (about 1 large head, 450g)
- 1/2 teaspoon fine salt, plus more to taste
- 1/4 teaspoon black pepper
- 1/4 teaspoon ground nutmeg
- 1/2 teaspoon dry mustard powder
To finish
- 2 1/2 cups sharp cheddar, grated by hand (about 8 ounces, 225g)
- Extra cheddar and crusty bread, to serve
Buy a block of sharp cheddar and grate it yourself. Bagged shredded cheese is tossed with starch so it will not clump in the bag, and that coating is exactly what keeps it from melting smooth in a soup.
How to make broccoli cheese soup
- Melt the butter in a large heavy pot over medium heat. Add the onion and carrot and cook, stirring, for 5 to 6 minutes until soft but not browned. Add the garlic for 30 seconds.
- Sprinkle in the flour and stir for 1 to 2 minutes, until it smells toasty and coats the vegetables.
- Slowly pour in the broth, whisking all the time so no lumps form. Whisk in the milk and cream.
- Add the broccoli, salt, pepper, nutmeg and mustard powder. Bring to a gentle simmer, never a hard boil, and cook for 15 to 20 minutes, stirring now and then, until the broccoli is very tender.
- Press about a third of the broccoli against the side of the pot with a spoon, or pulse briefly with a stick blender, to thicken the soup while leaving plenty of pieces.
- Take the pot off the heat. Wait one minute. Stir in the cheese one handful at a time, letting each melt completely before adding the next.
- Taste and add salt if needed. Ladle into bowls, top with a little extra cheddar and serve with crusty bread.
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Tips that make the difference
- Never let the soup boil once the milk is in. A gentle simmer is enough to cook the broccoli.
- If the soup does turn grainy, take it off the heat and whisk in a splash of cream; a quick buzz with a stick blender can also smooth it.
- The soup thickens as it stands. Loosen it with a little warm milk.
- Cut the florets small so every spoonful has broccoli in it.
Variations
- Bread bowls. Hollow out small round crusty loaves and ladle the soup inside.
- Potato. Add one peeled diced potato with the broccoli for an even heartier soup.
- Smooth. Blend the whole pot before the cheese goes in for a velvety soup.
- Cauliflower. Use half broccoli and half cauliflower florets.
Storage and make-ahead
Refrigerate leftover soup in a covered container for up to 4 days.
Reheat gently over low heat, stirring and adding a splash of milk. Do not let it boil or the cheese will split.
Cheese soups can turn a little grainy after freezing. If you freeze it, do so before adding the cheese, and stir the cheese in after reheating.
Frequently asked questions
Why did my broccoli cheese soup turn grainy?
The cheese was added while the soup was boiling, or too much went in at once. Take the pot off the heat and add hand-grated cheese a handful at a time.
Can I use frozen broccoli?
Yes. Use about 16 ounces of frozen florets, chop them small and simmer for only 8 to 10 minutes.
How do I make it thicker?
Simmer a few minutes longer before the cheese goes in, or mash more of the broccoli into the soup.
Which cheese is best?
Sharp or extra sharp cheddar from a block. Mild cheddar melts fine but tastes flat in a soup.
Broccoli, a roux, the pot off the heat and the cheese a handful at a time. Make it on the first cold night and drink it from a mug at the window.
Broccoli Cheese Soup That Never Turns Grainy
Thick, creamy homemade broccoli cheese soup with sharp cheddar, onion and carrot. The secret: the pot comes off the heat and the cheese goes in a handful at a time, so it melts smooth and never turns grainy.
Ingredients
- 4 tablespoons unsalted butter
- 1 medium onion, finely chopped
- 1 medium carrot, peeled and grated or finely diced
- 2 cloves garlic, minced
- 1/3 cup all-purpose flour
- 3 cups chicken or vegetable broth
- 2 cups whole milk
- 1/2 cup heavy cream
- 5 cups small broccoli florets, stems peeled and chopped
- 1/2 teaspoon fine salt, plus more to taste
- 1/4 teaspoon black pepper
- 1/4 teaspoon ground nutmeg
- 1/2 teaspoon dry mustard powder
- 2 1/2 cups sharp cheddar, grated by hand
- Extra cheddar and crusty bread, to serve
Instructions
- Melt the butter in a large heavy pot over medium heat. Add the onion and carrot and cook, stirring, for 5 to 6 minutes until soft but not browned. Add the garlic for 30 seconds.
- Sprinkle in the flour and stir for 1 to 2 minutes, until it smells toasty and coats the vegetables.
- Slowly pour in the broth, whisking all the time so no lumps form. Whisk in the milk and cream.
- Add the broccoli, salt, pepper, nutmeg and mustard powder. Bring to a gentle simmer, never a hard boil, and cook for 15 to 20 minutes, stirring now and then, until the broccoli is very tender.
- Press about a third of the broccoli against the side of the pot with a spoon, or pulse briefly with a stick blender, to thicken the soup while leaving plenty of pieces.
- Take the pot off the heat. Wait one minute. Stir in the cheese one handful at a time, letting each melt completely before adding the next.
- Taste and add salt if needed. Ladle into bowls, top with a little extra cheddar and serve with crusty bread.
