Combine buttermilk, cayenne pepper, chili powder, lime zest, 1 grated garlic clove, black pepper, and 1/4 cup chopped cilantro.
Cut the cod fillet into strips and submerge them in the buttermilk marinade. Cover with plastic wrap and let it sit in the refrigerator for at least 2 hours.
Meanwhile, begin making the Baja cream by combining the sour cream, mayonnaise, rice vinegar, black pepper, and 1 grated garlic clove.
Chop the cabbages, carrot, and cilantro. Place it into a bowl and toss it with the Baja cream. This will be your slaw.
Combine flour and baking powder.
Fill a skillet with about 1-2 inches of oil and bring it to medium high heat.
Dredge each cod fillet into the flour mixture and fry in the hot oil about 2-3 minutes per side. Transfer to a plate lined with paper towels to absorb and excess oil.
Assemble your tacos immediately. Using the tortilla of your choice (corn or flour) add the Baja cream slaw, then place 2 crispy cod fillets and top it with extra cilantro, pico de gallo, or guacamole.