📖 Instructions

1. Preheat your oven to 375°F (190°C). Grease a 9x13 inch baking dish with cooking spray. This prevents sticking and makes cleanup a breeze.
2. In a large skillet, melt 2 tablespoons of butter over medium heat. Add 1 diced onion and cook until softened, about 5 minutes. Now's the time to let those onions get happy and translucent, not burnt!
3. Add 2 cloves of minced garlic to the skillet and cook for another minute, until fragrant. Oh, the aroma! Garlic just makes everything better, don't you think?
4. Stir in 1/4 cup of all-purpose flour into the skillet. Cook for 1-2 minutes, stirring constantly, to create a roux. This will help thicken our luscious cheese sauce.
5. Gradually whisk in 2 cups of milk and 1 cup of chicken broth. Continue whisking until the mixture is smooth and begins to thicken. Patience is key here – no lumps allowed!
6. Bring the sauce to a simmer, then reduce heat and cook for 5 minutes, stirring occasionally, until it thickens slightly. You'll notice it coats the back of a spoon nicely when it's ready.
7. Remove the skillet from the heat and stir in 4 cups of shredded cheddar cheese until melted and smooth. Add 1/2 teaspoon of salt, 1/4 teaspoon of black pepper, and a pinch of nutmeg. Taste and adjust seasonings as needed. Is it cheesy perfection? It should be!
8. In a large mixing bowl, combine 4 cups of cooked broccoli florets, 2 cups of diced cooked chicken, and half of the cheese sauce. Gently toss to combine. Make sure everything is coated evenly in that deliciousness.
9. Pour the chicken and broccoli mixture into the prepared baking dish, spreading it evenly. Get it all in there!
10. Drizzle the remaining cheese sauce over the chicken and broccoli mixture. We want every bite to be cheesy and amazing.
11. In a separate bowl, combine 1 cup of panko breadcrumbs and 2 tablespoons of melted butter. Sprinkle the breadcrumb mixture evenly over the casserole. This will create a golden, crispy topping.
12. Bake in the preheated oven for 20-25 minutes, or until the casserole is bubbly and the topping is golden brown. Keep an eye on it – ovens can vary!
13. Let the casserole cool for 5-10 minutes before serving. This gives it a chance to set up a bit and makes it easier to serve. Enjoy!