Preheat your oven to 400°F (200°C). Cut the tops off the garlic cloves, drizzle with olive oil, wrap in foil, and roast for about 30 minutes until golden and soft.

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

Squeeze the roasted garlic cloves into the pot, discard skins. Pour in broth and add thyme, stirring together. Simmer for about 2 minutes.

Reduce heat to low and let the soup simmer for 15-20 minutes, stirring occasionally.

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

Stir in heavy cream, adjust seasoning with salt and black pepper, and warm through for a few minutes.

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