I always make lasagna in stages: make the sauce & refrigerate; make the filling(s) & refrigerate; grate the cheeses & refrigerate, etc. I even make the noodles ahead, and here’s how.
Line a large baking sheet with plastic wrap or parchment. Boil the noodles in a large pot of generously salted water until only half-done. One by one, pull the noodles from the pot and arrange on the baking sheet, layering with more plastic as needed. let stand at room temp for several hours or cover and refrigerate overnight.
Pulling them from the pot at half-done means they won’t stick to each other and won’t tear or fall apart coming out of the water. The moisture on the noodles will further soften them. They’ll be just right for the assembly and finished cooking as the lasagna bakes.
