Cut the raw fish into chunks and place in a pan with the milk.
Bring to the boil and then remove from heat..
Prepare the vegetable and gently fry until softened.
Remove the fish with slotted spoon.
Add flour and butter to milk and whisk over gentle heat until thickened.
Place half the mixture with the vegetables and add the cooked fish, defrosted shellfish, creme fraiche and pesto.
Layer the mixture with the lasagne.
Top with the remaining white sauce and grated nutmeg if liked.
Cook for about 30-40 minutes Gas 5 or 180.
Serve with grated parmesan.
Disclaimer:The nutritional information provided is approximate and is calculated using online tools. Information can vary depending on various factors, but we have endeavoured to be as accurate as possible.