Ingredients:
- 4 Tbsp Unsalted Butter
- 1 medium Yellow Onion, finely diced
- 2 medium Carrots, peeled and diced
- 2 Celery Stalks, diced
- 1/3 cup All-Purpose Flour
- 3 cups Chicken Stock (low sodium)
- 1/2 cup Heavy Cream
- 3 cups Cooked Chicken Breast or Thighs, shredded or diced
- 1 cup frozen Peas
- 1 tsp Dried Thyme
- 1/2 tsp Dried Rosemary
- 1 Bay Leaf
- 1 tsp Kosher Salt (or to taste)
- 1/2 tsp Freshly Ground Black Pepper
- Option A (Biscuit Topping): 1 1/2 cups All-Purpose Flour, 2 tsp Baking Powder, 1/2 tsp Salt, 6 Tbsp Cold Unsalted Butter (cubed), 3/4 cup Buttermilk
- Option B (Puff Pastry Topping): 1 sheet thawed Puff Pastry
- Egg wash (1 egg mixed with 1 Tbsp milk) for topping
Instructions:
- Preheat oven to 400°F (200°C). Lightly grease a 9x13 inch casserole/baking dish.
- Melt butter in a large, deep oven-safe skillet or Dutch Oven over medium heat. Sauté onion, carrots, and celery until softened, about 6-8 minutes.
- Stir in flour, thyme, and rosemary. Cook the mixture (the roux) for 1 minute, stirring constantly.
- Slowly whisk in the chicken stock until smooth. Bring to a simmer and cook until the sauce thickens enough to coat the back of a spoon (about 5 minutes). Discard the bay leaf.
- Stir in the heavy cream, cooked chicken, and frozen peas. Season generously with salt and pepper. Taste and adjust seasoning.
- Pour the entire chicken filling mixture into the prepared casserole dish.
- Prepare the topping: If using Biscuit Topping, drop spoonfuls or roll out dough to cover 75% of the filling surface. If using Puff Pastry, roll slightly larger than the dish, place over the filling, crimp edges, and cut 3-4 steam slits.
- Brush the topping evenly with the egg wash.
- Bake for 35–40 minutes, or until the topping is beautifully golden brown and the filling is bubbling.
- Let the casserole rest for 10 minutes before serving.