Preparation

• Preheat your oven to 375–400 °F (190–200 °C). Slice the top off the head of garlic to expose the cloves, then drizzle with olive oil and season with salt and pepper. Wrap the garlic in aluminum foil and roast it for 40–45 minutes, until it’s tender and caramelized, creating a sweet aroma in your kitchen.
• While the garlic is roasting, bring a large pot of water to a boil. Carefully add the peeled and diced russet potatoes, cooking them until they are fork-tender, about 15-20 minutes. Once cooked, drain the potatoes and set them aside.
• In a large pot or Dutch oven over medium heat, melt 4 tablespoons of butter. Once melted, add the chopped onions and leeks. Sauté until the vegetables are softened and translucent, about 5-7 minutes.
• Lower the heat to medium and stir in ¼ cup of all-purpose flour. Cook for about 1 minute, stirring continuously until the flour is lightly golden.
• Gradually whisk in 4 cups of chicken or vegetable broth, 1 cup of milk, and ½ cup of heavy cream. Add 1 teaspoon of dried thyme, seasoning with salt and pepper to taste. Continue to heat the mixture until it begins to thicken slightly, about 5-7 minutes.
• Once the soup is thickened, add the drained potatoes and squeezed roasted garlic cloves to the pot, along with 1 cup of grated Parmesan cheese. Purée the soup until smooth using an immersion blender or in batches in a regular blender. Adjust the consistency with additional broth as needed.
• Butter one side of each slice of bread. Place 1 cup of grated Gruyère cheese on the non-buttered side of two slices, then close with the other slices, buttered side out. Heat a skillet over medium heat, cooking the sandwiches until they are golden brown and the cheese has melted, about 5 minutes per side.
• Ladle your steaming bowls of Roasted Garlic Potato Soup. Garnish with additional Parmesan cheese and chopped chives. Cut the grilled cheese sandwiches into croutons and place them on top of the soup.