Preheat oven to 425°F (220°C). Set a baking/cooling rack (make sure it's oven-safe) in a baking sheet. If you don't have one, you can just line the baking sheet with parchment paper.
Take three shallow bowls. In one, combine the panko, garlic powder, onion powder, paprika, and peanut oil. Stir until the oil coats the breadcrumbs.
In the second bowl, beat the egg with the milk. Finally, in the third, add the flour.
If your chicken breasts are really thick, first cut them in half so you have two thinner pieces. Then cut the chicken into long strips (or short strips; this is really up to you. Just try to ensure they are around the same size so they cook evenly).
Season the chicken on both sides with salt and pepper.
One by one, coat the chicken pieces in the flour, then the egg mixture, and finally the panko mixture. Set the breaded chicken on the baking rack.
When all your chicken is breaded, bake in the preheated oven for 15-20 minutes until chicken is crispy and cooked through.
Serve immediately with your choice of condiments.