But, why is it so important to get the cooking time just right? Well, my friends, it's all about the chemistry - when you cook lasagna, the starches in the pasta break down, and the cheese melts and browns. If you undercook it, the pasta might be a bit hard, and if you overcook it, the cheese can be dry and rubbery.
So, how do you know when it's done? A good rule of thumb is to check the lasagna after 25-30 minutes, and then every 5-10 minutes after that. You're looking for a nice, golden-brown crust on top, and a hot, bubbly center.
How Long to Cook Lasagna in Oven: Perfect Timing Guide