Preheat oven to 400 °F
Mix the flour, garlic powder, Onion salt, and 2 tablespoons of the Parmesan Cheese together in a dredging plate.
Whisk the egg, 1 tsp of the lemon juice and mayonnaise in a separate dredging bowl.
Melt the butter in the heavy frying pan. (Medium to high heat)
Dredge the fish pieces in the egg mixture, followed by the flour mixture, making sure to evenly coat each cod piece.
Fry the breaded cod pieces in the pan for 1 to 2 minutes per side, creating a crispy coating on each side.
Remove the fish from the pan and set aside.
Add garlic and saute for a few seconds.
Add the broth and lemon juice to the hot pan, whisking to lift the browned bits.
Whisk in the cream and 1/4 cup of the Parmesan cheese.
Return the cod to the pan and turn off the heat.
Divide the remaining Parmesan cheese,(except 2 tbsp) between the pieces of cod.
Bake for approximately 20 minutes (or until flaky and an internal temperature of 145F)
Remove from the oven and sprinkle with remaining Parmesan cheese.
Serve hot.
Garnish with fresh slices of lemon and chopped parsley (optional)