Combine the fish marinade in a small bowl and mix well.
Score the fish by making deep diagonal lines with a sharp knife. Pour the marinade on it and rub generously, including the cavity and slits. You can place some lemon slices or fresh thyme into the belly of the fish. Set aside.
Add the tomatoes, capers, olives, pinch of salt and little olive oil to the baking dish and stir to combine.
Place the fish on it and bake at 400℉ for 30 minutes until it flakes easily.
While it's baking, combine the ingredients for the Ladolemono sauce in a small jar and shake well to combine.
When the fish is fully cooked, remove it from the oven and serve it on a platter. Pour the sauce all over the fish as you like with the cherry tomatoes, capers, and olives. Spoon some juice from the fish on it. Enjoy.
Video
Notes
If you can, choose cooking the whole fish and not the filet. Doing this helps keep the fish juicy and more flavorful.
Don't forget to slit the fish on both sides. This helps that beautiful marinade get in and also cooks the fish much more evenly.
Keep an eye on the fish at the 20-25 minute mark to check if it is done. High oven temperatures can cause the fish to cook pretty quickly, and you don't want to have overcooked fish.
If you have the skin to have a nice bit of char on the outside, turn on the broiler setting in your oven for the final 3-4 minutes of cooking.