In the morning, or preferably a minimum of an hour before cooking, place tilapia filets in a sandwich bag with juice of half a lemon, 4 sprigs of fresh dill, and the remains of the juiced lemon. Set in refrigerator to marinate.
When ready to prepare the fish, preheat oven to 375.
Place two tablespoons of butter, divided, in the bottom of a 9x9 pan.
Trim the ends of the asparagus and place asparagus in the bottom of the dish around your butter.
Place fish on top of butter pats.
Sprinkle with sea salt and red pepper.
Slice the remaining half lemon, and place slices and dill from the marinade on top of the fish.
Place in oven to bake. Bake approximately 20-30 minutes depending on the size of your filets. When the fish is flaky and white it is done.