Celebrity chef Giada DeLaurentiis.
The Lasagna Tip Giada De Laurentiis Gave To The Royal Family

At an event in 2011, Prince William asked Giada De Laurentiis where he'd gone wrong when he'd tried (but failed) to make an impressive lasagna for his wife, Catherine.

The "Everyday Italian" host told him there were two keys to remember when making lasagna: Put plenty of sauce on top and let it rest before you slice into it.

An adequate amount of sauce on top will help it develop a crust and keep the top noodles from drying out and becoming hard from the oven's heat.

Then there's the tip to let your just-out-of-the-oven lasagna sit undisturbed for a bit. This step is key in ensuring the pasta dish will hold its shape once you cut into it.

A lot of the liquid will seep out if you cut it right away, leaving you with limp pieces. Give it 10 to 15 minutes to rest so the liquids will absorb back into the lasagna.