Wrap Jalapenos and tomatillos in foil. Place foil over the comal or griddle. Roast on one side and then flip your foil over. Once the tomatillos and Jalapenos are nice and roasted, you take them off of the heat.
Some people like to peel off the chard, I leave it in. Gives it a smokey flavor. In your blender, add the Jalapenos, tomatillos, garlic, onion,cilantro. Blend well. Add salt and pepper to taste. If you don't like it too chunky add a couple of tablespoons of water.
Cool in refrigerator. You can add cilantro to garnich or add avocado chunks.