In a large pot, heat the butter and olive oil over medium heat.
Add the chopped onion, celery, and minced garlic.
Sauté for about 5 minutes until the vegetables are soft.
Stir in the all-purpose flour to the pot with vegetables.
Cook and stir for 1 minute to combine well.
Slowly pour in the chicken broth while whisking continuously.
Add the half-and-half and keep stirring until the mixture thickens slightly.
Add the chopped cooked chicken to the pot.
Stir in shredded carrots, chopped spinach, salt, black pepper, and thyme.
Simmer the mixture gently for a few minutes.
Add the gnocchi to the soup.
Continue to cook for about 5 minutes until the gnocchi is tender and the soup is heated through.