6 boneless, skinless, chicken breasts
1 1/2 C sharp cheddar cheese, grated
3/4 C milk
1/2 C parmesan cheese, grated
3 Tbsp unsalted butter
2 Tbsp all-purpose flour
1 1/2 Tbsp whole grain mustard
1/2 tsp garlic powder
Kosher salt and freshly ground pepper, to taste
Preheat oven to 375 F degrees.
Season chicken breasts generously with salt and pepper. Place in a large baking dish.
Cover with aluminum foil. Bake for 20 minutes.
In a large saucepan, melt butter over medium heat. Whisk in flour. Cook roux for 2 minutes, stirring constantly, until smooth, paste-like, and golden in color.
Remove from heat and gradually whisk in milk, until smooth.
Return to heat and bring to a boil.
Reduce heat to low and simmer for 5-7 minutes, or until thickened.
Stir in cheeses, mustard, and garlic powder. Season with salt and pepper.
Pour evenly over top of chicken.
Return to oven and bake another 25-30 minutes, or until chicken is cooked through.