Crispy Pacific Cod with Parmesan-butter Dipping Sauce

1 lb. Pacific cod, skin removed and cut into 2.5-inch-long pieces
2 tsp. olive oil
Kosher salt
1/2 cup corn flakes, crushed
1 stick of unsalted butter
1/4 cup grated Parmesan

Heat oven to 400. Rub the cod with the oil and season with 1/4 tsp salt. Dip the top side of the fish pieces (not the bottom side, from which the skin has been removed) in the corn flakes and place on a parchment or foil-lined baking sheet. Bake until just cooked through and opaque, about 10 minutes. In a small saucepan, melt the butter. Stir in the Parmesan and 1/4 tsp salt. Serve butter with fish for dipping.