Remove the stems and seeds from chile cascabel and tear into two pieces. Remove just the stems from chile de arbol, if any. Transfer to a preheated comal(griddle) pan, at medium heat, to toast. This is a fast process. As soon as the chiles begin to become aromatic, remove them from the skillet.
To that same skillet at medium heat, add the tomatoes, flat side down onto hot surface. Also add the onion and garlic. Drizzle in 2 tsps. of avocado oil. Roast, turning as needed for about 10 minutes.
Pour in 3 cups of water to the tomatoes. Add the dried chiles back into the skillet. Bring up to a light simmer and cook for 10 minutes. Turn the heat off cover the skillet. Let the ingredients steep while you clean the shrimp and prepare the slaw.
After you peel and clean your shrimp, season lightly with salt and pepper and chill until ready to use. Combine all of the ingredients for the slaw. Cover and chill. Prepare the chipotle crema. Cover and set aside.
Using a slotted spoon, transfer all of the ingredients from the skillet to the blender jar. Pour in 1/2 cup of the cooking water. Season with salt, to taste. Blend on high until smooth.
Preheat 2 tablespoons of avocado oil in a skillet at medium heat. Once it is hot, pour in the salsa from the blender jar. Rinse out the blender jar with 1/2 c of water. pour it into the skillet. Stir well to combine. Bring it up to a light simmer. Taste for salt. Cook for 10 minutes.
Preheat 2 tablespoons of oil to medium/high heat in another skillet for a few minutes. Remove shrimp from refrigerator. Once oil in the skillet is hot, add the shrimp in a single layer. Season lightly with salt and pepper. Cook for 4 minutes, turning halfway through cooking time. Pour in 1/4 c of the chile cascabel salsa. Stir well to coat all of the shrimp. Serve with warm corn tortillas, slaw, chipotle crema and extra cascabel salsa or a spicy red salsa. Store the extra cascabel salsa in a glass jar refrigerated for up to two weeks.