Cheesy Curry Chicken Bake

Preheat oven to 350 degrees F.
Heat oil in a large skillet over medium heat. Add the onion, celery, and carrots and cook until softened, for about 10 minutes. Stir in the garlic and cook for 1 minute.
Remove the cooked vegetables from the skillet and add the butter into the pan, allowing it to fully melt. Whisk in the flour, 1/4 tsp sea salt, and 1/4 tsp pepper. Cook for 1 minute. Slowly pour in the chicken bone broth while continuing to whisk. The liquid should begin to thicken as it gently boils. Stir in the sour cream and 2 cups shredded cheese and whisk until cheese is melted.
Into the cheese sauce, stir in the diced chicken, cooked rice, curry powder, garlic granules, 1/2 tsp sea salt, and 1/2 tsp pepper, along with the cooked vegetables that were set aside. Mix everything together.
Pour the mixture into a 9×13 baking dish, or a similar size dish. Top with the remaining 1/2 cup of cheese.
Bake for 25-30 minutes, or until the cheese is melted through and the casserole is bubbly along the edges.