Preheat the oven to 350°
Cook linguine 1-2 minutes short of package directions, so they are perfectly al dente. Drain and add back to pot.
Meanwhile, in a saute pan, cook onions and garlic in a drizzle of olive oil until translucent, about 3-4 minutes. Add in chicken, onion powder, garlic powder, oregano, parsley, and salt and pepper. Cook until chicken is no longer pink, about 5-6 minutes.
Add chicken to the pot with pasta. Add in cream of chicken, cream of mushroom (or cheddar), sour cream, chicken stock and butter. Mix until all ingredients are combined.
Pour pasta into a greased 13x9 casserole dish and top with cheese.
Bake for 35-40 minutes or until the cheese is beginning to brown and bubble.
Serve immediately