Chicken Tortilla Soup

2 1/2 cups chicken broth
6 corn tortillas, cut into 1/2 inch strips, divided
1 can green enchilada sauce
1 can red enchilada sauce
1 teaspoon ground cumin
2 cups cooked chicken, chopped
½ cup whole milk or half & half
Sour cream
Diced avocado

Combine chicken stock and half of the tortilla strips in a large pot. Cook over medium heat until strips soften and broth thickens slightly. Most of the tortilla strips will dissolve away. Stir in green and red enchilada sauces and cumin, and remaining tortilla strips. Stir in chicken and milk; heat through but do not boil.

Divide soup among four bowls and garnish with sour cream and avocado, if desired.