Preheat the oven to 200°C/Fan 190°C/Gas 6
Cut the fish fillets into finger-shaped portions.
In a large bowl, season the fish finger pieces with a bit of salt and pepper.
Ensure your flour, egg, and breadcrumbs are in three separate bowls next to each other.
Dip each fish fillet in flour, then beaten egg and finally breadcrumbs.
To cook the fish fingers, place them on a baking tray and bake for 20 minutes, turning halfway through.
Meanwhile prepare the tomato tartare sauce by mixing all the other ingredients in a bowl.
And, in another bowl, season the lettuce leaves in olive oil, salt and pepper, and parmesan
Create a sandwich by putting down two slices of bread, cover with tartare sauce, and top with lettuce.
Place lettuce and gherkins on the bottom slice, then put fish fingers on top. Finish with the other slice of bread.
Serving Suggestions: Serve with additional lettuce and tomatoes on the side.