Buffalo Ranch Chicken Broccoli Casserole

1 Stick Butter

1/2 Onion, diced
2 heads of Broccoli, cut into florets
1 cup finely chopped Carrots
1/2 cup Flour
2 cups Milk
2 cups Chicken Broth
1/2 Rotisserie Chicken, shredded

2 cups cooked Rice (recipe for 1 cup raw rice)
8 oz Extra Sharp Cheddar Cheese, shredded, divided
2 Tablespoons Frank's Red Hot Sauce, plus more for topping
2 Tablespoons Ranch Dressing Mix
3/4 teaspoon Garlic Powder
3/4 teaspoon Kosher Salt
1/2 teaspoon Black Pepper
3/4 cup Panko breadcrumbs
1 Tablespoons Butter, melted

Preheat oven to 400 with rack 6 inches from heat source.

Melt butter in large pan. Cook onions, broccoli, carrots, and garlic in butter for 5 minutes. Add flour with a whisk. Gradually stir in milk and chicken broth; cook over medium heat, stirring constantly, until thick.

Add chicken, rice, 1/2 of the cheddar cheese, Frank's, ranch dressing mix, garlic powder, salt, and pepper, stir until cheese is melted. Remove from heat. Transfer to a 13x9 baking dish.

Stir together panko and butter in a small bowl. Add remaining cheese. Sprinkle evenly over chicken mixture.

Bake until casserole is bubbly, about 18-20 minutes. Increase temperature to broil. Broil until top is golden brown, 1-2 minutes. Remove from oven and let cool 5 minutes. Sprinkle with additional Frank's.