Lightly oil pan. Set aside. Use paper towel to pat fish dry. In a small bowl, mix together minced garlic, thyme, and parsley. Set aside. (if you wanted it sweet, add 2 tbsp honey too)
Slice lemons. Thinly slice red onion into rings. Lay lemons on baking pan. Place fish on top of lemon slices, with each fish fillet having 2 slices underneath. Top each fillet with a pinch of the salt, pepper, and chili flakes (if desired for heat).
Spread the parsley mixture on top of the fillets. Top each fillet with two thinly sliced pieces of butter. Layer the sliced olives (if you want to add some of those) and sliced onions on the fillets.
Bake at 375°F for 15-20 minutes or until the center of the fillet is flaky and cooked thoroughly. Insides should be white and not grey (that means you cooked too long if there is grey on any areas)