# Components:
→ Protein & Vegetables
01 - 2 cups cooked chicken breast, diced or shredded
02 - 3 cups fresh broccoli florets
→ Sauce & Base
03 - 2 tablespoons unsalted butter
04 - 2 tablespoons all-purpose flour
05 - 1 cup whole milk
06 - 1/2 cup low-sodium chicken broth
07 - 1 teaspoon Dijon mustard
08 - 1/2 teaspoon garlic powder
09 - 1/2 teaspoon onion powder
10 - 1/2 teaspoon salt
11 - 1/4 teaspoon black pepper
→ Cheese & Topping
12 - 1 1/2 cups sharp cheddar cheese, shredded (divided)
13 - 1/2 cup panko breadcrumbs
14 - 1 tablespoon olive oil
→ Optional
15 - 1/4 teaspoon crushed red pepper flakes
# Method:
01 - Preheat oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish with butter or nonstick spray.
02 - Steam or blanch broccoli florets in boiling water for 2 to 3 minutes, until just tender and bright green. Drain well and set aside.
03 - In a medium saucepan over medium heat, melt unsalted butter. Whisk in all-purpose flour and cook for 1 minute, stirring constantly until no raw flour remains.
04 - Gradually add whole milk and chicken broth to the roux, whisking steadily to prevent lumps. Simmer for 3 to 4 minutes, stirring frequently, until sauce thickens.
05 - Stir Dijon mustard, garlic powder, onion powder, salt, and black pepper into sauce. Remove from heat.
06 - Add 1 cup shredded cheddar cheese to the hot sauce and stir until fully melted and the sauce is smooth.
07 - In a large mixing bowl, combine cooked chicken, drained broccoli, and cheese sauce. Mix thoroughly to coat ingredients.
08 - Evenly spread chicken-broccoli mixture into the prepared baking dish.
09 - Sprinkle remaining 1/2 cup shredded cheddar cheese evenly over the filling.
10 - In a small bowl, toss panko breadcrumbs with olive oil, adding red pepper flakes if desired. Distribute the mixture evenly over the cheese.
11 - Bake in the preheated oven for 25 to 30 minutes, until casserole is bubbling and the top is golden brown.
12 - Allow casserole to cool for 5 minutes before slicing and serving.
