Make the chipotle lime crema. In a medium bowl, whisk together the sour cream, adobo sauce, lime juice, and salt. Season to taste with additional salt if desired. Set aside.
Make the dredging mixture and batter. In a bowl or deep plate, combine the flour, salt, pepper, and garlic powder. Whisk to combine. In a separate bowl or deep plate, combine the flour, salt, pepper, cumin, and garlic powder and whisk to combine. Whisk in the beer and hot sauce until smooth.
Heat a large nonstick skillet over medium-high heat and add the oil. Dredge the fish pieces in the flour, shake of the excess, and dip in the batter, shaking off the excess as well. Fry for 2 or so minutes per side, or until golden and crispy, depending on the thickness of your fish. Be careful not to overcrowd the pan, to ensure optimal crispiness! Repeat until all fish has been fried.
To serve, place a small handful of shredded cabbage in the tortilla, top with a few pieces of fish, avocado, a drizzle of chipotle crema, and a handful of fresh cilantro. Serve immediately with extra lime wedges!