Preheat oven to 350℉. To cook the kale and dandelion-green mixture, heat olive oil in a medium-sized frying pan over medium heat. Once it’s shimmering, add onion and fennel and sauté until softened, about 7 minutes.
Stir in dandelion greens and kale, and cook just until wilted. Stir in salt and pepper and remove from heat.
Beat the egg into the ricotta cheese until blended. Stir in nutmeg and pepper.
Cook the lasagne noodles just until al dente, or use oven-ready noodles.
Spread 1/2 cup of ricotta in the bottom of a 9 x 13 baking dish. Layer four lasagna noodles over top, three lengthwise and one crosswise at the end. Spread half the pesto over the noodles (I find a fork works well), followed by half the remaining ricotta. Sprinkle lightly with mozzarella. Layer another four lasagne noodles on top.
Spread the dandelion and kale filling over the noodles and sprinkle liberally with mozzarella. Layer four noodles on top.
Spread the remaining pesto over the noodles, followed by the remaining ricotta. Sprinkle with mozzarella. Place the final layer of noodles on top. Spread with the remaining mozzarella and parmesan.
Bake uncovered for one hour, covering the top with a piece of parchment if it is browning too quickly. Let sit for about 10 minutes before cutting in and serving.