Green Chile Sauce for Pork or Chicken Tamales

1 large chopped onion
4 cloves minced garlic
1 (15 ounce) can tomatoes, drained
2 cups diced green chilies (roasted and peeled if you are using fresh)
3 large tomatillos, husks removed
2  jalapeno peppers, roughly chopped
1 cup 3water OR 1 cup chicken broth (broth is not traditional, but I like the flavor better)
2 tablespoons ground cumin (or to taste)
2 tablespoons ground chili powder (or to taste) (optional)
1 teaspoon salt (omit if using chicken broth)

Place tomatillos in boiling water and cook for about 10 minutes or until soft. Place all ingredients in a blender and process until smooth. If needed, add more water until desired consistency. Pour over cooked and shredded meat