Broccoli Cheese Soup

Ingredients:
1/2 cup butter
1 onion, chopped
2 (16 ounce) packages frozen broccoli florets
4 (14.5 ounce) cans chicken broth
1 (1 pound) loaf processed cheese food, cubed
2 cups half and half
1 tablespoon garlic powder
2/3 cup cornstarch
1 cup water

Directions:
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 half and half and garlic powder.
In a small bowl, stir cornstarch into water until dissolved. Stir into soup; cook, stirring frequently, until thick.