I've been told this is the objectively wrong temp, but I usually crank it to around 400 with a cover. An actual cover with room for the air to circluate, not foil...foil gives me the ragies with lasagna lol, and I prop the corningware on top of another pan so the bottom doesn't get too hot and burn things up. I take the top off after like 30 minutes (for the big dish, anyway, less for the smaller one) and then do another 10-15 with the top off. Hit it with a little broiler action if it's not sufficiently browned, but don't usually need to. I also find low moisture, whole milk mozzarella is the best for the top because it doesn't give off all that excess moisture like fresh would, but has a lot more gooey deliciousness than a part skim mozzarella would. Also, I mix in a bechamel that has some added cream cheese to it with my sauce and go REALLY HAM with it. The noodles are too busy soaking up all that goodness to dry out That's how Nana Bunny taught me to do it as a kiddo when I helped her cook and how I've kept doing it since then She was very secretive hehe.