Preheat the oven to 400°F (200°C). Prepare the garlic by slicing the tops off, drizzling with olive oil, wrapping in foil, and roasting for about 30 minutes until golden and soft.

In a large pot, heat 2 tablespoons of olive oil over medium heat. Add chopped yellow onion and sauté for 5-7 minutes until translucent.

Squeeze roasted garlic into the pot, discard skins, and add 4 cups of broth along with fresh thyme. Simmer gently for about 2 minutes.

Reduce heat and let the soup simmer for 15-20 minutes, allowing flavors to meld.

Remove thyme sprigs and blend the soup until smooth using an immersion blender.

Return the blended soup to low heat. Stir in 1 cup of heavy cream and adjust seasoning with salt and pepper.

Ladle soup into bowls and garnish with fresh herbs or croutons. Serve with crusty bread.