Place tomatillos, serranos, jalapeños, ¼ piece onion, garlic, arbol chiles and Roma tomato on a 2-foot long piece of aluminum foil. Bring edges of foil together, making a pouch. If contents of pouch fall out, add another sheet of foil to close. Place pouch in a large skillet over medium heat. Heat for 10 minutes, turn pouch over for another 10 minutes, making sure the color on tomatillos has darken a bit.  Transfer everything in pouch to blender. Add cilantro  and 1 cup water to blender. Blend until smooth.

Heat 1 tablespoon oil in a large pan over medium heat. Arrange panela cheese slices on hot pan. Lightly fry until a golden brown crust forms on both sides. Remove from heat and set aside.

In a separate skillet, heat 1 tablespoon oil over medium heat. Pour in blended salsa and a 1 cup water. Season with garlic salt, ½ teaspoon pepper, oregano and cumin. Stir and simmer for 10 minutes.

Season shrimp with salt and remaining black pepper. Heat remaining tablespoons of oil in a large skillet over medium heat. Add shrimp and season with paprika. Cook shrimp for 4 minutes, stirring frequently or until pink and cooked through. Remove from heat and set aside.

Arrange roasted panela cheese pieces in a large molcajete. Add 1 to 2 cups warm salsa. Add shrimp and lightly stir to coat. Serve with warm corn tortillas and roasted green onion.