Start with preparing the garlic aioli. Combine the mayonnaise, garlic, lemon juice, salt and chipotle powder. Mix well and put in the fridge until the burgers are done.
Preheat the oven to 425° and spray a baking sheet with oil.
Get three bowl for the breading. In the first bowl put 1/4 cup flour. In the second bowl, whisk the egg. In the third bowl combine the cornflake crumbs, 1/4 cup flour, garlic powder, smoked paprika and salt.
Take a piece of chicken and coat in the flour. Then the egg, and then the cornflake mixture. Make sure the chicken is well coated in the cornflake crumbs. repeat this until all the chicken is coated.
Place the chicken on the oiled baking sheet and either spray the chicken with oil or brush it with oil.
Bake the chicken for 30 minutes, flipping it halfway through.
Take the burger buns and spread the mayo on each side. Layer the lettuce, then the chicken, tomatoes and finally the onion. Top with the other half of the bun and enjoy!