Boil the seeded guajillo chiles, the serrano pepper, and the tomatoes.

Slice the pork into strips and set aside.

Once the guajillo chiles are ready, add them to a blender with a splash of vinegar, the orange juice, 2 cloves of garlic, the adobo seasoning, and half the onion sliced into thin strips. Blend until smooth.

For the salsa, blend the tomatoes and the serrano pepper together.