Melt the butter with the olive oil in a large stockpot or Dutch oven over medium. Add the onion, celery, and carrots and cook for 5 minutes, stirring occasionally, until tender but not browned. Stir in the garlic and flour and cook for 1-2 minutes until the flour loses its raw taste.
Whisk in the evaporated milk, dried thyme, garlic powder, onion powder, salt and pepper. Bring to a boil and reduce to medium and cook until thickened. Add the gnocchi, chicken, and spinach. Cook for 5-7 minutes or until the gnocchi are cooked, stirring occasionally. Serve topped with the Parmesan cheese.