Thaw shrimp, peel and devein, and blot with paper towels so they are dry to the touch, the seasoning will stick better. If you want to "stretch" the shrimp for more servings cut the shrimp into smaller pieces.

Prepare all the toppings as shrimp cook quickly and you'll want to plate everything as soon after heating or cooking shrimp. (depending on if they are pre-cooked or raw)

Toss shrimp with taco seasoning.

Heat a skillet, I prefer cast iron it gives shrimp a great flavor and the shrimp don't "steam" they get a delicious crisp on the edges, it helps dry them a bit especially if they were previously frozen as they seem to absorb water.

Cook (or heat) shrimp, it'll only take a few minutes.

Heat the tortillas, corn tortillas can be heated for a few seconds in the microwave to make pliable or use a comal or flame of a gas burner. Avoid heating flour tortillas in the microwave unless they are older and dryer, fresh flour tortillas will get too soft and floppy and won't hold up as well, they are best heated on a comal or over a flame.

Line up your tortillas in a tortilla holder or just lay them flat and try to curve up the edges so each one is holding up the other.

Place cabbage and onion in the bottom of the tortillas.

Next, add the shrimp, and top with cheese, avocado, and topping or sauce of your choice. I've listed more options in the post.