Preheat oven to 375°F (190°C).
Blend tofu, lemon juice, nutritional yeast, garlic powder, salt, and plant-based milk until smooth. Set aside.
Heat olive oil in a skillet. Sauté garlic and spinach until wilted. Stir into the tofu ricotta.
Spread ½ cup marinara sauce on the bottom of a baking dish.
Add a layer of lasagna noodles, followed by tofu ricotta, then sauce. Repeat until all ingredients are used.
Sprinkle vegan mozzarella on top, if using.
Cover with foil and bake for 30 minutes. Remove foil and bake another 15 minutes.
Let sit for 10 minutes, then garnish with basil. Serve hot!