Prepare the manicotti shells according to package directions, then rinse and drain.

Thaw the frozen spinach, squeeze out excess water, and chop.

Chop the white mushrooms, shiitake mushrooms, and onions.

Sauté the red bell peppers in red wine until softened.

Sauté garlic with the mushrooms, onions, and red bell peppers until fragrant and tender.

In a bowl, combine the chopped spinach, sautéed mushroom mixture, fat-free cottage cheese, Italian herbs, and grated fat-free Parmesan cheese.

Mix all ingredients thoroughly to ensure even distribution of flavors.

Carefully stuff the manicotti shells with the prepared mixture.

Place the stuffed shells in a baking dish.

Pour spaghetti sauce over the noodles, ensuring they are well covered.

Bake in a preheated oven at 400°F (200°C) for approximately 45 minutes, or until the pasta is tender and the sauce is bubbly.