Preheat the oven to 400°F (200°C) and line a baking sheet with nonstick foil or parchment; set aside.
In a shallow dish combine the crushed fried onions, grated Parmesan, panko, and garlic powder; mix to an even coating.
In a separate shallow dish whisk the eggs with the mayonnaise and water until smooth.
Place the flour in a third shallow dish.
Dredge each chicken tender in flour, shaking off excess, then dip into the egg mixture, and press into the fried-onion mixture to coat completely. Transfer to the prepared baking sheet.
Lightly spray the coated chicken tenders with cooking spray and arrange in a single layer on the baking sheet.
Bake for 20 to 25 minutes, until the chicken is cooked through and the coating is golden and crisp.