In a large bowl, whisk together the flour, baking powder, salt, garlic powder and pepper.
2 cups all purpose flour, 1½ tablespoon baking powder, 1 tablespoon kosher or sea salt, 1 teaspoon garlic powder, ½ tablespoon fresh ground black pepper
Add the beer and egg and whisk until smooth. Add more beer if needed, until batter has the consistency of thick pancake batter.
Pat the fish fillets dry with paper towels. Cut pieces lengthwise into 1-inch thick strips. Season with salt and pepper.
1 large egg, 8 to 10 ounces beer (don't use a light or dark beer)
Heat oil in a large deep skillet to 375 degrees F (190 degrees C). To test if it’s hot enough, add a drop of the batter into the oil; if it sizzles when you drop it in, it’s ready.
Using a pair of tongs, dip the fish pieces into the batter to coat; lift out and let excess drip off.
Fry fish in batches (do not crowd the pan) until golden brown, turning occasionally if needed, 3 to 4 minutes. It’s ready when the flesh is easily flaked with a fork.
Drain on paper towels.
Make the tacos: On a hot corn tortilla, add about 2 tablespoons of crema, layer with shredded cabbage, add a piece of fish, pickled onions, avocado, hot sauce and lime juice. Sprinkle cilantro for extra flavor. Enjoy hot!