Preheat grill to medium-high heat. Place fish in a medium size dish. Whisk together the oil, lime juice, ancho, jalapeno, and cilantro and pour over the fish. Let marinate for 15 to 20 minutes.
Remove the fish from the marinade place onto a hot grill, flesh side down. Grill the fish for 4 minutes on the first side and then flip for 30 seconds and remove. Let rest for 5 minutes then flake the fish with a fork.
Place the tortillas on the grill and grill for 20 seconds. Divide the fish among the tortillas and garnish with any or all of the garnishes.
Preheat grill or use side burners of the grill. Heat oil in medium saucepan, add onions and garlic and cook until soft. Add tomatoes, serrano and jalapeno and cook until tomatoes are soft, about 15 to 20 minutes. Puree the mixture with a hand-held immersion blender until smooth and cook for an additional 10 to 15 minutes. Add the hot sauce, oregano, cilantro and lime juice and season with salt and pepper, to taste.