In a large pot, melt 2 tablespoons of butter over medium heat. Add 1 chopped onion and 2 minced garlic cloves; cook for about 5 minutes until the onion becomes translucent and fragrant.

Add 4 diced starchy potatoes and 4 cups of vegetable broth to the pot. Bring to a gentle boil then reduce the heat to simmer for 15-20 minutes until the potatoes are fork-tender.

Once the potatoes are tender, stir in 8 cups of fresh spinach and cook for 2-3 minutes until wilted.

Transfer the soup in batches to a blender and blend until smooth and creamy, then return it to the pot.

Reduce the heat to low and whisk in 1 cup of heavy cream or coconut milk along with 1 tablespoon of butter until fully incorporated. Season with salt, pepper, and a pinch of nutmeg.

Ladle the soup into bowls and garnish with grated Parmesan cheese and fresh herbs.