Lentils boost our fibre intake and are delicious in this vegetarian take on a comfort food classic. By combining cooked red lentils with Marinara sauce, I make an easy 'lentil Bolognese' for layering in the dish.
Preheat oven to 375F. Lightly oil a 9x13 baking dish.
Bring a large pot of salted water to a boil and cook the lasagna noodles according to the package directions. Drain, rinse and cool the noodles.
Stir the red lentils into the Marinara sauce, then spread a cup of sauce on the base of the baking dish. Top with a quarter of the cooked lasagna noodles.
Wilt the spinach in a pan with the butter, then chop and add to the ricotta. Crack an egg into the mix and stir to combine. Season with salt and pepper.
Spread the ricotta mixture over the layer of lasagna noodles. Top with more noodles to cover. Add 2 cups of lentil bolognese, followed by the last of the noodles.
Top with the remaining lentil bolognese, spreading it evenly over the noodles. Sprinkle the parmesan and cheddar cheese over the top. Arrange the tomato slices on the cheese, then pop the pan in the oven.
Bake for 35-45 minutes or until the lasagna is bubbling around the edges and the cheese is melted and golden. Remove form oven. Let sit for 15 minutes before slicing and serving.