Preheat the oven to 375°F.

Heat the tortillas, wrapped in damp paper towels, in the microwave for 30-45 seconds.

Place the warmed tortillas in 4 inch diameter ramekins or bowls.

Place in the oven and bake for 12-15 minutes.

To prepare the ceviche, add the lime juice, grapefruit juice and orange juice to a glass or stainless steel bowl.

Add the mahi mahi and onions, make sure all of the fish is covered in the citrus juice.

Cover the bowl and place in the refrigerator for 20-30 minutes.

While the fish is “cooking” in the citrus juice, combine the tomatoes, jalapenos, cilantro and sea salt in a large mixing bowl.

After 20-30 minutes, use a strainer to drain the fish from the juice, then add it to the bowl, with the other ingredients.

Gently stir in the avocado.

Spoon the ceviche into the taco bowls.