In a large pot, heat olive oil over medium heat until shimmering. Add chopped yellow onion and sliced leek, and cook for about 3-5 minutes until softened and translucent.

Incorporate sliced brown mushrooms and minced garlic into the pot. Sprinkle with salt and black pepper, and sauté for an additional 5 minutes until mushrooms turn golden.

Add peeled and cubed potatoes, followed by veggie broth and dry white wine. Bring to a gentle simmer, cover, and cook for 15-20 minutes until potatoes are tender.

Remove the bouquet of fresh herbs, then stir in grated Parmesan or nutritional yeast, along with heavy cream or plant-based cream. Allow the cheese to melt.

Let the soup cool slightly, then carefully transfer it to a blender or use an immersion blender. Blend until reaching desired consistency.

Ladle the creamy Ratatouille Soup into bowls and garnish with additional grated Parmesan and fresh herbs. Serve hot with crusty bread or a light salad.