Chicken and Rice Casserole

1 cup chopped onion

4 boneless, skinless chicken breasts

1/2 teaspoon black pepper, divided

1 (14-ounce) can fat-free, less-sodium chicken broth

1 tablespoon butter

1 (8-ounce) zucchini, halved lengthwise and thinly sliced

1 (8-ounce) yellow squash, halved lengthwise and thinly sliced

2 cups cooked long-grain white rice

1 teaspoon minced fresh rosemary

1 1/2 tablespoons all-purpose flour

1 1/2 cups 2% reduced-fat milk

1/2 cup (2 ounces) grated fresh pecorino Romano cheese, divided

1/4 teaspoon salt

In a crockpot, place the chicken breasts. Pour on top the rice, onion and zucchini. Season with salt and pepper. In a glass measuring cup place the flour and milk, whisk to combine. Pour over the top. Pour in the broth. Mix in the seasonings and cheese. Cover and cook on low for 6 hours. 30 minutes Prior to serving place 1 C bread crumbs on the top. Serve with grated cheese.