Once you remove the lasagna from the oven it is important to let it sit for a minimum of 10 minutes. If you have the time, it is even better to wait 20 before cutting and serving. It needs time to "set-up." This makes the slices neater, and it won't burn your tongue. Simply cut the casserole across into quarters, and then across into eight squares. Use a flexible spatula and a second knife to help slide it off the spatula onto the plate.