Fill a small saucepan half full of water and add the chiles. Bring to a boil, cover, and simmer until the chiles are softened, about 5 minutes. Drain and discard the water, remove stems from the chiles. Remove the seeds by rinsing under water.

Add the cooked chiles to the container of a blender. Add the garlic and water, and season lightly with salt. Puree until smooth.

In a separate covered stew pan with a lid, add the vegetable oil and heat. Add the chicken or pork pieces, and brown for about 15 minutes. Pour in the adobo sauce, add the sprig of oregano, and cover the stew pot. Lower the heat, and allow to simmer for 25-30 minutes.

Serve over rice