Blanche the lasagna noodles according to the package instructions. Set aside and let cool.
In a pan set over medium heat, melt the butter and cook the leeks, mushrooms, and garlic for 5 minutes, stirring occasionally. Season with salt and pepper, add the white wine and reduce by half. Add the seafood and pinch of nutmeg. Simmer for 2 minutes. Set aside.
In a pot set over medium heat, bring the cream to a low boil. Add the flour and ½ cup of Saputo Mozzarellissima cheese. Using a whisk, stir until mixture is smooth. Season with salt and pepper.
Add the leek and seafood mixtures to the cream, stir, and remove from heat.
Cover the bottom of an oven-safe casserole dish with approximately 1 cup of the sauce.
On a working surface, lay out the lasagna sheets. Spread approximately ¼ cup of the mixture over top and roll sheets up.
Place the lasagna rolls in the casserole dish and pour the remaining sauce over top.
Top with remaining Saputo Mozzarellissima cheese and Saputo Parmigiano Reggiano cheese. Place in the centre of the oven and bake 30 minutes.