Whisk egg and milk together in a large bowl. Place all of your thinly sliced chicken into the bowl, ensuring it is all covered. Place the bowl in the fridge for 30 minutes to an hour.
Heat a pan on the stove over medium heat with avocado oil for about five minutes or until warm. Preheat the oven to 450℉.
While the pan is heating, mix together cassava flour, paprika, garlic powder, onion powder, dried herbs, salt and pepper in a large bowl and place next to the stove.
Remove the chicken from the refrigerator and place the bowl next to the cassava flour mixture.
Piece by piece, move chicken from the milk to the flour using a fork and coat each piece in the flour completely.
Carefully transfer the chicken to the skillet and cook for 5-7 minutes on each side. The skillet should be hot enough to sizzle as you add the chicken to it. Tip: if the bottom of your pan is coated in excess flour after cooking a batch, clean out pan and start the oil heating step again to achieve clean, not burnt, chicken.
Move the chicken to a baking sheet with parchment paper. Top each piece with 1-2 tbsp marinara sauce and a sprinkle of mozzarella cheese.
Bake for 5-10 minutes, watching to ensure the cheese melts and doesn’t burn.
Garnish with salt, pepper and fresh basil and serve with pasta and salad, if you’d like!