Broccoli Cheddar Soup With Cheesy Croutons

Step 1

Halve2 onions. Peel and coarsely chop. Peel and smash4 garlic cloves, then coarsely chop. No need to break out your best knife skills because it’s all going to get blended, but try to cut everything into somewhat even pieces so they cook at the same rate.

Step 2

Melt3 Tbsp. unsalted butterin a large Dutch oven or pot over medium-low heat. Add onion, garlic, and½ tsp. red pepper flakes; season withsaltandblack pepper. Stir to combine, then cover pot and cook, stirring occasionally, until softened and just starting to take on color, 8–10 minutes.

Step 3

Meanwhile, trim bottoms of2 heads of broccoli, then peel. Separate hefty stalks from florets (the thin, little stalks attached to broccoli tops are fine to leave attached to the crowns). Set aside florets. Coarsely chop stalks into 1"–2" pieces. Peel1 medium russet potato. Coarsely chop into 1"–2" pieces.

Step 4

Add broccoli stalks and potato pieces to pot and stir to coat in butter. Pour in5 cups water, add1 Tbsp. salt, and bring to a boil over high heat. Reduce heat to medium-low and keep at a simmer. Cover pot and cook until broccoli stalks and potatoes are completely tender (test with a cake tester, paring knife, or fork), 20–25 minutes.

Step 5

Meanwhile, chop reserved florets into small pieces (you can take the time to separate them into baby florets or just have at them with your chef’s knife). Grate8 oz. sharp cheddar cheeseon the large holes of a box grater. You should have about 2 1/2 cups.

Step 6

Add half of florets to pot, cover, and cook until bright green, 3–5 minutes. Transfer to a blender, let cool for 5 minutes, and purée until smooth. Some blender advice: Don't fill your blender more than halfway—work in batches as necessary. To avoid explosions, remove the center lid from the blender and cover with a kitchen towel. Alternatively, use an immersion blender. Your soup won’t be quite as smooth, but it will still be great. Return purée to pot.

Step 7

Return to medium heat and add remaining florets. Cover pot and cook until bright green, another 3–5 minutes. Add2 cups cheddar cheeseand stir until smooth. Cover and reduce heat to low; set aside while you make the cheddar croutons.

Step 8

Heat broiler. Broil4 thick slices rustic white bread(if using) on a rimmed baking sheet until lightly browned (watch closely: broilers vary dramatically in power!), 2–3 minutes. Turn bread over (soft side up), then sprinkle withreserved cheddar cheeseand a few flecks ofred pepper flakes. Continue to broil until cheese is bubbling and browned in spots, 2–3 more minutes.

Step 9

Remove soup from heat and stir in½ cup plain Greek yogurt. Season generously withblack pepper; taste forsalt.

Step 10

Cut cheese toasts (if using) into 1" (spoon-sized!) pieces. Divide soup among bowls. Top with cheddar croutons or reserved cheese.