Preheat the oven to 425 degrees.
Slice the leek and clean thoroughly.
Get a small saucepan going over medium heat, and add the olive oil, leeks and just a pinch of salt. Cook this for 15 minutes until the leeks are caramelized, stirring frequently.
While the leeks are cooking, get three shallow bowls out and in one place the egg (and scramble), in another add the flour, salt and pepper, and in the final dish add the panko and chopped herbs (mix together). I used a mix of mint, rosemary, thyme and parsley. Use what you like!
Cut the 9 oz. piece of fish in half (unless you already have two 4.5 oz. filets and pat the fish dry.
Then dredge the fish in the flour (shake off any excess), then the egg, and finally the panko + herb mixture.
Place the fish onto a baking sheet that is either lightly greased or has a silpat on it and pop in the oven for 10 minutes until the panko is just slightly browned.
Once the fish is cooked, top with the leeks and a squeeze of lemon and serve with a side of pasta or rice and something bright green!