Carefully wash fish fillets and drain on paper towels.
Preheat the oven to 400°F. Coat a large, rimmed baking sheet with 2 tablespoons vegetable oil.
Meanwhile, make the sauce. Process the mayonnaise, garlic clove and ½ teaspoon lemon zest in a food processor until smooth, about 15 seconds. Transfer to a small bowl and stir in the basil. Cover, and place in the refrigerator.
Place cereal in a resealable food-storage plastic bag, seal the bag, and finely crush the cereal with a rolling pin. Transfer crushed cereal to a large bowl and set aside. In another bowl, whisk the eggs with 2 tablespoons vegetable oil and the lemon juice; set aside. In a shallow dish, mix potato starch, salt, pepper, and ½ teaspoon lemon zest.
Dip fish in potato starch, coating well; shake off excess. Dip floured fish in egg mixture, then in cereal, coating all sides completely.
Place the coated fish onto the oiled baking sheet and bake until golden and crispy, about 15-20 minutes. Flip the fish halfway through, using tongs. When ready, transfer to a wire rack for 2-3 minutes to cool slightly before serving. Serve with sauce and lemon wedges.
Tip: For the fish fillets, it is best to use fresh, preferably bought from sustainable sources. If you are using frozen fillets, defrost them first. You can also use catfish, sole, or haddock. You can adjust the taste with a bit more salt or pepper depending on your preferences.