In a large pot or Dutch oven, melt the butter over medium-high heat.
6 tablespoons butter
Add the onion, carrots, and celery. Cook for about 5 minutes until softened. Stir in the garlic and cook for 1 more minute.
1 cup yellow onion, 1 cup matchstick carrots, 1 cup celery, 4 cloves garlic
Sprinkle the flour over the vegetables and stir well. Cook for 1 minute.
3 tablespoons all-purpose flour
Slowly whisk in the chicken broth and evaporated milk until the soup is smooth.
5 cups chicken broth, 12 ounces evaporated milk
Bring to a gentle boil, then add the shredded chicken, thyme, salt, and pepper.
3 cups shredded cooked chicken, 1 tablespoon fresh thyme, Salt and pepper
Reduce the heat and let the soup simmer while you prepare the dumplings.
In a mixing bowl, whisk together the flour, baking powder, salt, pepper, and thyme.
2 cups all-purpose flour, 1 tablespoon baking powder, Salt and pepper, 1 tablespoon fresh thyme
Stir in the milk and melted butter until a soft dough forms. Drop spoonfuls of dough onto the simmering soup—do not stir.
¾ cup whole milk, 4 tablespoons butter
Cover the pot and cook for about 15 minutes, until the dumplings are fluffy and cooked through.