After you peel and wash the tomatillos, transfer them to a saucepan. Add the chile peppers, onion and garlic. Cover with water. Bring to a boil, reduce to a simmer and cook for 10 minutes.

Using a slotted spoon, transfer to the blender. Add 1/2 cup of cooking water. Cover tightly and secure lid holding it down with a kitchen covering. Blend on high until smooth and strain through a wire mesh strainer. Set aside. Discard the water leftover in the saucepan and heat pan to medium. Add the oil and let heat for 2 minutes. Add the strained salsa, bouillon. oregano, salt and pepper to taste. When it comes to a boil, reduce and simmer for 10 minutes. Yields about 4 cups.