Prep the fish: Pat fish very dry with paper towels. Cut into even 1-inch bites.
Season lightly with salt and pepper.
Set up dredging: In one bowl, whisk eggs with water. In another, mix flour, panko, salt, pepper, paprika, and garlic powder.
Coat the bites: Toss fish in the dry mix, dip in egg, then back into the dry mix. Press gently so the coating sticks.
Place on a plate.
Make the aioli: Whisk mayonnaise, grated garlic, lemon juice, Dijon, a bit of water, and a pinch of salt and pepper until smooth. Adjust lemon and salt to taste. Chill.
Heat the pan: In a large nonstick or well-seasoned skillet over medium heat, add olive oil and 2 tbsp butter.
When hot and foamy, you’re ready.
Cook in batches: Add a single layer of fish bites. Don’t crowd. Cook 2–3 minutes per side until golden and just cooked through.
Transfer to a paper towel–lined plate. Repeat with remaining bites, adding a splash of oil if needed.
Finish with lemon butter: Reduce heat to low. Add 2 tbsp butter to the empty pan.
Once melted, add lemon zest and juice. Swirl for 30 seconds, then return all cooked bites to the pan and toss gently to coat. Sprinkle with parsley.
Taste and adjust: Add a pinch of salt or an extra squeeze of lemon if needed.
Serve immediately with garlic aioli and lemon wedges.