http://allrecipes.com/recipe/13045/broccoli-cheese-soup/

• 1/2 cup butter
• 1 onion, chopped
• 1 (16 ounce) package frozen chopped broccoli
• 4 (14.5 ounce) cans chicken broth
• 1 (1 pound) loaf processed cheese food, cubed
• 2 cups milk
• 1 tablespoon garlic powder
• 2/3 cup cornstarch
• 1 cup water

In a stockpot, melt butter over medium heat. Cook onion in butter until softened. Stir in broccoli, and cover with chicken broth. Simmer until broccoli is tender, 10 to 15 minutes.

Reduce heat, and stir in cheese cubes until melted. Mix in milk and garlic powder.

In a small bowl, stir cornstarch into water until dissolved. Stir into soup; cook, stirring frequently, until thick.

From comments on original recipe:

• I doubled the cheese and the broccoli, used 1/2 and 1/2 instead of milk and I cut the cheese into small cubes for quick melting. It was incredible, and I will absolutely be making this soup often. For family or for guests, watch out–this will knock your socks off! Word of caution: after cheese has melted, turn stove heat down to low or the cheese will stick to the bottom of pot.