Mango Avocado Salsa:
Heat a dry small saucepan over medium-high heat. Cut kernels off the cob, and add corn to the hot skillet in a single layer, allowing to blister 2 to 3 minutes before tossing. Cook for 2 more minutes.
Transfer to a medium bowl. Add remaining ingredients, and carefully stir until combined.
Marinate for 30 minutes, tasting and seasoning accordingly. Set aside while preparing catfish.
Pour milk or egg in a shallow bowl or plate, and stir in garlic powder, salt and chili lime seasoning.
In a second bowl, add panko. Dip each fillet in milk or egg mixture and then panko.
Heat olive oil in skillet over medium-high heat. Pan-sear catfish fillets for 3 minutes on each side. Transfer to a paper towel-lined plate, and carefully slice each fillet into 2 to 3 pieces.
To serve, add a pinch of lettuce to each tortilla, followed by piece of catfish and generous spoonful of salsa.