Ingredients:

  • 3 cups shredded rotisserie chicken
  • 3 medium zucchini (courgettes), thinly sliced
  • 1 small yellow onion, finely chopped
  • 3 cloves garlic, minced
  • 1 tsp fresh thyme leaves
  • 1 Tbsp olive oil
  • 4 Tbsp unsalted butter
  • 4 Tbsp all-purpose flour
  • 2 cups whole or 2% milk, warmed
  • 1/2 cup chicken stock
  • 1 tsp Dijon mustard
  • Salt and freshly ground black pepper, to taste
  • 1 cup sharp cheddar cheese, grated
  • 1/2 cup Gruyère cheese, grated
  • 1/2 cup Panko breadcrumbs
  • 2 Tbsp fresh parsley, chopped

Instructions:

  1. Preheat oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish.
  2. Heat olive oil in a large skillet. Sauté the onion until soft (about 5 minutes). Add garlic and thyme; cook for 1 minute. Add sliced zucchini and cook until slightly softened, about 5-7 minutes. Remove vegetables and set aside.
  3. In the same skillet, melt the butter over medium heat. Whisk in the flour and cook for 1-2 minutes to form a roux.
  4. Slowly whisk in the warm milk until the sauce thickens significantly and coats the back of a spoon (Béchamel sauce).
  5. Remove the sauce from the heat. Stir in the chicken stock, Dijon mustard, salt, and pepper.
  6. Gently fold the shredded rotisserie chicken, the sautéed zucchini/onion mixture, and half of the grated cheese into the creamy sauce.
  7. Pour the entire mixture evenly into the prepared baking dish.
  8. Sprinkle the remaining cheese evenly over the top. Cover the dish tightly with foil and bake for 20 minutes.
  9. Remove the foil. Sprinkle the Panko breadcrumbs over the cheese. Bake uncovered for another 10–15 minutes, or until the topping is golden brown and the centre is piping hot.
  10. Let the casserole rest for 5–10 minutes before serving. Garnish generously with fresh parsley.