3 1.5 inch thick halibut filets - cut into cubes.
Lay the cubed halibut on parchement paper on a large baking sheet. drizzle lemon on each piece, Then drizzle olive oil on each piece. On both sides of the filet cubes, sprinkle spice generously. Allow the seasoned filet cubes to sit for 10 minutes. Preheat the grill on high for 10 minutes. Place halibut on the grill. Cook 5-6 munutes per side. Halibut should be 140 degrees internally. Always use a meat thermometer for safety.
When done, remove from grill. place the corn tortillas on the grill. They will only need approx 30 seconds per side.
Build your taco..Place halibut chunks, onions and guacamole on each tortilla. Add green salsa or salsa fresca if desired. I think they are perfect like this.