• Step 1: Preheat your oven to 375°F (190°C). Slice the zucchini lengthwise into 1/4-inch thick strips, being careful not to cut them too thin or they may tear.
• Step 2: In a medium bowl, mix together the ricotta cheese, 1/2 cup of the mozzarella cheese, the Parmesan cheese, egg, garlic, basil, salt, and pepper until well combined.
• Step 3: Lay the zucchini strips on a clean surface and spoon a heaping tablespoon of the ricotta mixture onto the lower third of each strip. Carefully roll up the zucchini around the filling, starting from the bottom and rolling up towards the top.
• Step 4: Spread 1 cup of the marinara sauce in the bottom of a 9×13 inch baking dish. Arrange the zucchini roll ups seam-side down in the dish, then top with the remaining 1 cup of marinara sauce and the remaining 1/2 cup of mozzarella cheese.
• Step 5: Bake for 30-35 minutes, or until the zucchini is tender and the cheese is melted and bubbly. Allow to cool for 5 minutes before serving.