Zucchini Noodles with Marinara, Mushrooms & Greek Yogurt

Sauté half a yellow onion and a whole carton of sliced mushrooms with a little cooking spray or 1 tablespoon of olive oil, salt, and pepper until softened. Then, ribbon 3 zucchinis with a veggie peeler and simmer them on medium-low heat for 2-3 minutes. You might need to drain out some liquid from the zucchini. Then, top the zucchini and mushroom mixture with marinara sauce and a dollop of plain nonfat Greek yogurt. Finish with 1/4 cup of part skim shredded mozzarella if desired.