If your chicken breasts have attached cutlets, detach them. Slice each breast in half horizontally to create thinner pieces. Pat them dry with a paper towel for better seasoning adhesion.
Season both sides of the chicken breasts and cutlets with salt, pepper, onion powder, and paprika, ensuring each piece is lightly but evenly coated with the spices.
Cut the chicken into 2-inch cubes.
Whisk the eggs in a shallow bowl. In a separate bowl, combine the ground flax seeds and grated Parmigiano Reggiano, if using.
Dip each seasoned chicken cube into the beaten eggs, ensuring it’s fully coated. Then, roll the chicken in the flax seed mixture, pressing lightly to ensure an even coating.
Arrange the coated chicken pieces on a greased or lined baking sheet. If you have a backing rack, lightly coat it with oil and use it on your baking sheet. Bake for 25-30 minutes or until the chicken is no longer pink on the inside and the internal temperature reaches 165°F (74°C).