Wash the zucchini and mushrooms thoroughly. Slice the zucchini into half-moons about ¼ inch thick and cut the mushrooms into ½-inch slices. Thinly slice one medium onion and mince two cloves of garlic.

Place a large skillet over medium heat and add 2 tablespoons of olive oil. Once the oil shimmers, gently stir in the sliced onions and cook for about 3 minutes until they begin to soften.

Add the minced garlic and sliced mushrooms to the skillet. Stir frequently and allow them to cook for 3-4 minutes until the mushrooms are tender.

Introduce the zucchini slices into the skillet. Season with salt, pepper, and 1 teaspoon of dried thyme. Stir everything together and sauté for an additional 3-5 minutes.

Taste the sautéed zucchini, mushrooms, and onions and adjust the seasoning if necessary. Garnish with fresh parsley and serve warm.