I made this recipes for smoked salmon lasagne with Scottish cold smoked salmon but equally you can make it with hot smoked salmon. I've also added mushrooms to mine, to be honest I wasn't sure whether it would work but my family wolfed it down so I guess that's a “yes!”.
There's a little bit of prep work to do to make the cheese sauce and to cook the mushrooms but after that it's simply a matter of layering everything together and baking for about 45 minutes.
Note also that I've used “no pre cooking required” lasagne sheets, it's just so much easier in my book. Also, I haven't added any salt and that's because there's a significant amount in the smoked salmon. I found the results to be seasoned pretty well in this way so my advice would be to taste it before adding additional salt.
Quantities of smoked salmon and cheese can be varied to your taste so see how you go. There's enough here to serve 4 main portions – I used a casserole dish approx 10” x 7”.
Melt 20g of the butter in saucepan, add the sliced mushrooms, season with pepper and cook for 5 minutes until soft. This will extract any moisture so you'll need to remove them from the pan with slotted spoon and put to one side.
Melt remaining 40g butter, add the flour and whisk over gentle heat until smooth then remove from the heat and slowly add the warm milk to create smooth sauce. Return it to the heat, bring to the boil whisking all the time until sauce thickens then reduce the heat and cook for 1 - 2 minutes, continue stirring. Finally take it off the heat and stir in mozzarella cheese and double cream – that's the sauce done.
To assemble the smoked salmon lasagne
Put a layer of sauce on base of your casserole dish and sprinkle with ¼ of the cheddar cheese.
Place lasagne sheets on top (3 approx.)
Pour over a “layer” of sauce and sprinkle with another ¼ of cheddar cheese
Cover with a half of the tomatoes, half of the cooked mushrooms and half of the salmon
Repeat 2, 3 and 4 and finish with 2 and 3.
Bake for 45 - 55 minutes at or 190°C (375°F) until the cheese begins to brown and place it under the broiler for a final 5 minutes if you want that crispy top to your smoked salmon lasagne.