Preheat oven to 425 degrees Fahrenheit.
Spray a shallow baking pan with nonstick spray and set aside.
Thinly slice two lemons and place slices in a single layer in the greased baking pan.
Arrange fish on top of lemon slices.
Brush cod with the melted butter.
Season the cod with salt and lemon pepper to taste.
Bake 17-19 minutes or until fish is opaque and flakes easily.
While fish is baking, melt the 2 tablespoons of butter in a skillet over medium heat.
Add the panko crumbs and cook for 2-3 minutes or until golden brown, stirring constantly.
Remove from heat and add two tablespoons of oil, dill, one teaspoon of salt and juice from half of a lemon.
Stir until well-combined.
Transfer fish to a serving plate or platter (discarding the lemon slices) and squeeze the juice of ½ a lemon over the fish.
Top with the panko crumb mixture and serve immediately with lemon wedges.