1-First, preheat your oven to 375°F (190°C) to get things started on the right note. This temperature ensures even cooking without drying out the layers. Peel and thinly slice the sweet potatoes, setting them aside for easy layering.

2-Next, in a bowl, combine the ricotta cheese, feta cheese, minced garlic, chopped basil, chopped sage, red pepper flakes, salt, and pepper to make the filling. Lightly grease an 8×8-inch baking pan with olive oil to prevent sticking. Spread the marinara sauce evenly on the bottom of the pan.

3-Then, layer the first set of sweet potato slices over the sauce, followed by half of the ricotta mixture and 1 cup of baby spinach. Add a second layer of sweet potato slices, the remaining ricotta mixture, and the rest of the spinach. Top with the final layer of sweet potatoes, then sprinkle on the shredded mozzarella and Parmesan cheese.

4-Bake uncovered for 35 minutes, and cover with foil if the cheese starts to brown too quickly. In the last minute, add more fresh sage on top for extra flavor. Let the lasagna rest for 15 minutes after baking to make slicing easier, then garnish with chopped parsley if you like. Preparation time is 20 minutes, cooking time is 35 minutes, and total time is 55 minutes this recipe yields 4 large or 6 smaller servings, making it ideal for various meal sizes.