Although traditional lasagna is made with a layer of ground beef, there is no rule saying this dish has to be made with meat, especially if you’re a vegetarian. Indeed, replacing the meat with one or more vegetables is a common tactic, and one that works especially well is broccoli rabe lasagna, as professional chef and cookbook author David Tanis has proven.
We recognize that at first glance, this may seem a little odd. Many vegetarian lasagnas use spinach or zucchini, both of which lend themselves well to seamlessly fitting into lasagna layers without creating bumps. But broccoli? That would be bump city. That’s why Tanis actually cooks the broccoli first, then takes the leaves and grinds them into a pesto, which he then spreads on the lasagna. He also finely chops up the rest of the broccoli so that it matches the size and bulk of ground beef, allowing it to join the rest of the lasagna without standing out.
You can assemble this vegetarian lasagna by starting with lasagna sheets at the bottom of the pan, adding a layer of béchamel followed by the ricotta mixture, and finishing with the chopped broccoli topped with the broccoli pesto. Repeat the process until all ingredients have been used up.