تشيكن نجتس منزلي

3 boneless chicken breasts
1 egg
1 tsp garlic powder
1 tsp onion powder
Salt & black pepper

1/4 cup cornstarch for first coating

Coating:
3/4 cup flour
1/4 cup cornstarch
1/2 tsp baking powder
Salt and black pepper
1 tsp onion powder
1 tsp garlic powder
1 tsp mustard
1 egg
1 cup water