Oven 400 deg F.

Finely slice washed leek and add to oven proof casserole pan with butter and swig of oil. Sweat for 10 mins.
Finely slice asparagus, saving the tips. add to pan, season well with salt and pepper, and sweat for a further 10 mins.
Add flour and mustard and mix.
Add milk and bring to boil, turn down to simmer. Add frozen veggies. Use potato masher to lightly crush ingredients.
Add roughly chopped mint and cheese (reserve some cheese for the top). Add asparagus tips.
Put in the lasagna noodles, mixing or submerging as you go.
Top with cheese, crushed blanched almonds lemon zest and a good swig of olive oil.
Bake in 400 deg F oven for 25 minutes.
Dot the top with basil pesto or fresh basil.
Cool for 10 mins then serve.