Make the salsa: Place the mango, red onion, jalapeno, lime juice, cilantro, salt, pepper, and cumin in a blender or food processor and pulse until finely chopped. Set aside in the refrigerator.

Place the peeled and deveined shrimp in a medium bowl and toss with taco seasoning and salt to evenly coat. (If using fish, mix the taco seasoning and salt together in the bowl, then gently dredge the fish in the seasonings until coated.)

Heat a medium saute pan over medium heat. Once hot, add the oil.

For shrimp: add the shrimp to the pan in an even layer and allow to cook for about 2-3 minutes. Turn the shrimp and continue cooking for another 1-2 minutes, until firm and pink.

For white fish: add to the pan and cook for 3-5 minutes. Flip and continue cooking for another 3-5 minutes or until fish reaches an internal temperature of 145°F.

Remove from the pan and set aside.

Toast the tortillas. This can be done in multiple different ways.

One way is to heat a small non-stick pan over medium-high heat and toast the tortillas one at a time until slightly browned around the edges, about 30 seconds - 1 minute per side.

If you have a gas stove, you can use tongs to place tortillas directly over a low flame, turning when brown spots begin to form on the tortillas.

When finished toasting, wrap the tortillas in a cloth napkin or tin foil to keep warm.

Assemble the tacos: Fill each tortilla with 3-4 shrimp, 1 Tbsp salsa and top with lettuce and tomato. Extra salsa can be stored in a container with a lid for about 3 days in the refrigerator.