Simple Greek Style Baked Fish

Name: Simple Greek Style Baked Fish
Cuisine: Greek
Ingredients: 2/3 lb halibut (cut in two portions); ½ white or yellow onion; 1 lemon; Strawberry tomatoes (or assorted cherry tomatoes); mixed olives (with or without pits); salt and fresh cracked black pepper; a little smoked paprika; a few red pepper flakes (optional); olive oil; white wine; fresh dill (or thyme, parsley, whatever you like); feta cheese (optional)