Classic Beef Lasagna

Why This Classic Beef Lasagna Works

During cooking, the onion and garlic soften in the hot oil and start to taste sweeter. When the ground beef browns with them, the meat firms up and loses its raw taste, and the tomato sauce clings better to the cooked beef. As the sauce simmers, water slowly cooks off, so the tomatoes, herbs, and meat thicken into a hearty bolognese that won’t run all over the pan.

While that happens, the butter and flour cook together and then grab onto the milk. As the milk heats, the flour swells and turns the béchamel into a smooth, thick sauce that can sit between the pasta layers without soaking straight through. A little nutmeg keeps it from tasting flat.

In the oven, the lasagna sheets finish softening as they sit between the hot bolognese and béchamel. The starch in the pasta and the melted mozzarella and Parmesan all set as they cool, so the layers stay stacked instead of sliding apart. Letting the lasagna rest those few minutes lets everything firm up, so neat slices hold together and the sauce stays inside the layers.

Mistakes To Avoid

Boiling the lasagna sheets until they are very soft makes them tear when layered. Once in the oven, these overcooked sheets turn mushy and the layers slide around instead of cutting into neat slices.

Letting the bolognese stay watery by not simmering it long enough leaves too much liquid in the dish. In the oven this extra liquid seeps out, so the lasagna looks soupy and the layers don’t hold together.

Overheating the butter and flour for the béchamel until it browns gives the sauce a grainy, pasty feel. When baked, this thick, rough sauce sets in clumps instead of forming a smooth, creamy layer between the pasta.

Pouring the milk into the béchamel all at once instead of gradually can create stubborn lumps. Those lumps don’t fully dissolve in the oven, so the finished lasagna ends up with rubbery pockets of floury sauce.