Cut the chicken breasts into bite-sized pieces or nugget shapes.
In a bowl, combine the buttermilk and chicken pieces. Make sure all the chicken pieces are coated with the buttermilk. Cover the bowl and refrigerate for at least 30 minutes (or up to 2 hours) to marinate.
In a separate bowl, whisk together the flour, salt, black pepper, paprika, garlic powder, onion powder, and cayenne pepper.
Heat about 2-3 centimeters (1 inch) of cooking oil in a deep skillet or frying pan over medium-high heat until it reaches 175°C (350°F).
Take each piece of marinated chicken from the buttermilk, allowing any excess to drip off, and then coat it thoroughly in the flour mixture, pressing the flour onto the chicken to adhere.
Carefully place the coated chicken nuggets into the hot oil using tongs. Make sure not to overcrowd the pan; fry in batches if necessary.
Fry the chicken nuggets for about 3-4 minutes per side or until they are golden brown and cooked through. The internal temperature of the chicken should reach 75°C (165°F).
Use a slotted spoon or tongs to remove the cooked chicken nuggets from the oil and place them on a plate lined with paper towels to drain any excess oil.
Serve the chicken nuggets hot with your favorite dipping sauces.Enjoy your homemade chicken nuggets!