Trim any excess fat off the chicken breasts, then cut into strips about 4 inches long, 1½ inches wide, and ½ inch thick. Try to make all chicken strips similar in size so they bake at the same rate. Set aside.
In a large bowl, stir together mayonnaise, gluten-free flour, egg, garlic powder, onion powder, paprika, salt, and ground black pepper. Stir until smooth and thoroughly combined.
Add the chicken to the mixture and toss until the tenders are uniformly coated. Let this sit for 10 minutes.
Preheat oven to 400°F (204°C). Line a large baking sheet with parchment paper.
Place the panko breadcrumbs on a large plate and coat the chicken tenders one piece at a time. Use a fork to gently press the panko into the chicken so the crumbs stick on well. As each chicken tender is coated, gently shake off any excess panko and place the chicken tender onto the prepared baking sheet.
Once all chicken tenders are coated in panko, place the baking sheet into the oven and bake for 15 to 18 minutes. The chicken tenders are done once the crust is lightly golden brown and the internal temperature reaches 165°F (74°C).
Notes
Make sure you’re using fresh, not frozen chicken breasts. The mixture won't stick to thawed chicken breasts that have too much moisture.
Panko breadcrumbs are the best choice for crispy chicken fingers, but if you can’t find gluten-free panko, you can substitute with regular gluten-free breadcrumbs. Just make sure they’re processed down to a fine crumb
Air fry instead? Preheat your air fryer to 400°F and air fry the chicken strips in batches for 10-12 minutes, flipping halfway through.
Feel free to mix up the seasonings! Instead of the garlic powder, onion powder, and paprika, try substituting a tablespoon of Italian seasoning or Herbs de Provence.