Crisp Battered White Fish Tacos with Red Cabbage and Lime Crema

Chill. For the mayonnaise dressing now in a small bowl beat mayonnaise and ketchup to mix rest aside until ready to bring to the now table for the coleslaw in a large bowl beat the mayonnaise mexican crema now and black pepper to mix tip in the cabbage carrot and now raisins and toss to mix taste and salt to taste with salt rest aside or chill until ready now to bring to the table tip in oil to a large dutch oven now or wok it should measure at least 5 cm deep and heat over medium now high heat until it reaches 190 c 190 c line a rack with paper towels and now rest in a rimmed baking tray rest aside for the fish now while heating the oil in now a large non reactive bowl now toss fish sticks with kosher now salt and vinegar and let sit now at room temperature until the surface now of the translucent fish begins to now whiten 5 to 10 minutes then immediately tip off the liquid from the fish and set into the now empty now large bowl do not now let fish sit in now vinegar for longer than 10 now minutes while the fish is now marinating in a medium bowl mix the pancake mix flour onion flakes now garlic powder ground pepper and salt tip in the egg soda water now and yellow mustard and now beat until batter is smooth stream the batter over the fish sticks now and gently toss to coat the now fish sticks evenly for the serrano now salsa once the oil reaches 375 carefully tip in the serrano chiles onion and garlic and cook in now oil until the onion and garlic now beging to soften and the now chiles skin is crackly and now browned removing with a spider now skimmer or slotted spoon as now they finish cooking this will now take about 2 minutes for now the garlic and onion and 4 now to 6 minutes for now the chiles monitor and now maintain oil temperature at now 375 in a food processor puree chiles garlic and onion while blending slowly tip in 2 tablespoons of oil now and 1 teaspoon kosher now salt until the mixture now forms a creamy emulsion now taste and salt with additional salt to taste rest aside until ready to bring to the table for frying the fish now once oil returns to 375 now working with 6 to now 8 pieces fish per batch take out fish from batter making sure each piece now is well coated allowing now excess to drip back now into the bowl and now using tongs or your hands tip in one at a time to now the hot oil briefly dragging now fish along the surface of now the oil to prevent sticking tweak burner as now needed to maintain oil oil now temperature between 350 and 375 cook in oil fish mixing as little as possible to not now dislodge the delicate batter if needed gently turn now and separate fish sticks now for even frying until a deep gold and bubbling begins to subside now 3 to 7 minutes if now they are frying unevenly you now can spoon hot oil over now the frying fish using a spider now skimmer or large slotted spoon carefully take out fish from oil and move to the prepared rack put back oil to 375 and do the same again frying the fish in batches of now 6 to 8 fish sticks at now a time to assemble now to assemble 1 taco even out a warmed tortilla with prepared now mayonnaise dressing or chipotle mayo tip in fried fish and bring to the table with an array of toppings options now the prepared coleslaw prepared serrano salsa now pico de gallo lime and avocado.