I love this recipe because it's lighter than traditional lasagna and is bursting with garden fresh flavor. Even a pasta-lover like myself doesn't miss the noodles! This recipe has a lot of steps, but since it freezes well, I try to always make one or two extra to keep in the freezer for dinner another night.
Technique tip: Using a mandolin to slice the zucchini makes quick work of it and ensures consistent slice thickness. You can wrap the assembled lasagna well with plastic wrap and then a layer of foil and keep in freezer for up to 2 months. Defrost overnight in refrigerator prior to baking.
For the zucchini:1.
Preheat grill to medium-high heat.2.
Lay zucchini slices in a single layer on paper towels and lightly sprinkle with salt. Let sit for an hour (this will help to draw moisture out of the zucchini). Pat with paper towels to remove water before preparing to grill.3.
Lightly brush zucchini slices on one side with olive oil and grind a dusting of fresh black pepper over the slices. Grill for 2-2½ minutes, turning once. Once cooked, transfer to a paper towel-lined tray, placing paper towels between each layer (ideally, you will do this the night before and refrigerate on covered tray overnight. This will help keep your lasagna from getting watery. If you do not have time to do this, be sure to pat off as much moisture as possible before assembling lasagna).
For the herbed ricotta:
Place ricotta in a fine-mesh sieve set over a bowl and let sit for an hour (or overnight in the refrigerator) to remove any excess liquid.
Combine all ingredients for ricotta, except the eggs, in a medium bowl. Taste and then beat in eggs until just combined. Set aside until ready to assemble.
For the sauce:
In a medium saucepan, heat 2 tablespoons olive oil over medium-high heat. Add onion and red pepper flakes and sauté until slightly translucent, approximately 2-4 minutes. Add garlic and sauté until fragrant, approximately 1-2 minutes. Add chicken sausage and brown, cooking through completely until no longer pink in the center. Break up large chunks of sausage with wooden spoon as it cooks. Add tomato paste and cook for a minute before adding tomatoes and oregano.
Cook until sauce has thickened, approximately 12-18 minutes. Add basil and salt and cook for a few more minutes. Adjust seasoning as necessary. Remove from heat until ready to assemble lasagna.
Preheat oven to 375°F.2.
Line the bottom of 8- by 8-inch glass baking dish with single layer of zucchini slices, slightly overlapping (depending on the length of the zucchini slices, you may need to add an extra strip or two in the opposite direction to fully cover bottom of baking dish).3.
Next, add layer of ricotta followed by layer of meat sauce. Repeat layers three times, alternating the direction of zucchini in each layer.4.
Finish with a top layer of zucchini. Place slices of mozzarella on top and sprinkle with 1/2 cup Parmigiano-Reggiano cheese.5.
Place on a baking sheet and cook in pre-heated oven for 40 minutes. Remove from oven and let sit for 15 minutes before cutting.