Step 1: Preheat oven to 375°F (190°C).
Step 2: Heat olive oil in a large skillet over medium heat. Add chicken and cook until browned, about 5-7 minutes. Remove and set aside.
Step 3: In the same skillet, add onion and garlic. Cook until softened, about 3 minutes.
Step 4: Add carrots and broccoli to the skillet. Cook for 5 minutes until slightly tender.
Step 5: Stir in frozen peas, cream of mushroom soup, chicken broth, sour cream, thyme, salt, and pepper. Mix well.
Step 6: Return chicken to the skillet and combine with the vegetable mixture.
Step 7: Transfer the mixture to a greased 9×13 inch baking dish.
Step 8: Sprinkle shredded cheddar cheese evenly over the top.
Step 9: In a small bowl, mix breadcrumbs with melted butter. Sprinkle over the cheese layer.
Step 10: Bake for 25-30 minutes until bubbly and the topping is golden brown.