Creamy Roasted Garlic Soup with Parmesan Crostini
Rich, mellow roasted garlic gives this creamy soup its deep, comforting flavor. Blended with tender potatoes, shallots, and cream, this roasted garlic soup has a smooth, velvety texture and a naturally sweet, savory finish. Toasted hazelnuts add a delicate crunch, while golden Parmesan crostini brings a satisfying contrast. Finished with fresh parsley and olive oil, it is perfect for a cozy lunch or comforting dinner.
25 min
75 min
🍽️ Servings: 2
Roasted Garlic Soup
Ingredients
- 125 g whole garlic heads, unpeeled
- 7.5 g extra virgin olive oil
- 5 g neutral oil
- 10 g unsalted butter
- 75 g shallots
- 175 g potatoes
- 375 g vegetable stock (or chicken stock)
- 120 g heavy cream, 60% fat
- ½ tsp dried thyme (0.5 g)
- Salt, to taste
Instructions
- Preheat the oven to 190 °C / 375 °F. Slice about 10 mm off the top of the garlic head to expose the cloves. Transfer to a small baking dish, season lightly with salt, and drizzle with the olive oil. Cover tightly with aluminum foil.
- Roast for about 45 minutes, until the garlic is completely soft. Remove the foil and roast for another 10 minutes, allowing the exposed cloves to develop a deeper golden color.
- While the garlic roasts, peel the shallots and finely chop them.
- Peel the potatoes and cut them into small, evenly sized pieces. Place them in cold water, gently stir with your hand, then replace the water with fresh cold water. Keep the potatoes submerged until needed.
- Heat the neutral oil and butter in a saucepan over medium heat. Add the shallots and cook for about 5 minutes, stirring occasionally, until soft and translucent without significant browning.
- Drain the potatoes and add them to the saucepan. Season with dried thyme and salt, then pour in the stock.
- Bring to a gentle simmer and cook for about 15 minutes, until the potatoes are completely tender.
- Remove the roasted garlic from the oven. Peel the softened cloves individually, or gently squeeze them out of their skins directly into the saucepan.
- Add the heavy cream and let everything simmer together briefly.
- Remove the saucepan from the heat and blend for about 2 minutes, until smooth and creamy. Avoid excessive blending, which can make the potatoes gummy.
- Pass the soup through a fine mesh sieve for a silky texture. Taste and adjust the salt as needed. If the soup is too thick, loosen it with a little additional hot stock.
Parmesan Crostini
Ingredients
- 60 g baguette
- 17.5 g Parmesan cheese, finely grated
- 5 g extra virgin olive oil
- Dried thyme, to taste
Instructions
- Preheat the oven to 200 °C / 400 °F.
- Cut the baguette lengthwise into a long slice about 1 cm thick.
- Brush with the olive oil, sprinkle with dried thyme, and generously cover with the grated Parmesan.
- Bake for about 8 minutes, until the bread is crisp and the Parmesan is golden.
Hazelnut and Parsley Topping
Ingredients
- 15 g hazelnuts
- 2.5 g extra virgin olive oil
- 2.5 g fresh flat leaf parsley, finely chopped
Instructions
- Toast the hazelnuts in a dry skillet over medium heat for about 5 minutes, until fragrant and lightly golden.
- Transfer the warm hazelnuts to a container, close the lid, and shake to loosen their skins.
- Remove the loosened skins. It is fine if a little remains.
- Roughly chop the hazelnuts and finely chop the parsley.
- Pour the hot soup into a bowl. Drizzle with olive oil, scatter over the parsley, and finish with the toasted hazelnuts.
- Rest the Parmesan crostini against the edge of the bowl and serve immediately.
Tips & More Info
Why roast garlic instead of using raw garlic?
Roasting softens garlic's sharp, pungent flavor and brings out a sweeter, more mellow character. The gentle heat also makes the cloves soft enough to blend smoothly into the soup. Deep golden garlic gives the soup a richer flavor, but avoid letting the exposed cloves turn dark brown or black, which can introduce bitterness.
Avoid overblending the potatoes
Potatoes release starch when cooked, and aggressive blending can make the soup sticky or gluey. A short, controlled blend is enough to create a creamy texture. If using a powerful blender, stop as soon as the soup becomes smooth.
Why use potatoes and cream together?
Potatoes provide body through their starch, while cream adds richness and a softer mouthfeel. Together, they create a thick, velvety soup without needing flour or another thickener.
Choose the right potatoes
Floury potatoes such as russets break down easily and help thicken the soup. Waxy potatoes hold their shape better and may produce a slightly lighter texture. Either works, but avoid overblending regardless of the variety.
Adjust the consistency after straining
The soup naturally thickens as it cools because of the potato starch. If it becomes too thick, stir in a little hot stock until it reaches your preferred consistency. Add liquid gradually so the roasted garlic flavor stays concentrated.
Why remove the hazelnut skins?
Hazelnut skins contain compounds that can contribute bitterness and a slightly dry sensation. Removing most of the skins gives the topping a cleaner, sweeter nutty flavor. A few remaining pieces are perfectly fine.
Keep the crostini crisp
Parmesan crostini absorbs moisture quickly when placed directly on hot soup. Resting it against the bowl's edge helps preserve its crunchy texture while keeping the presentation attractive.
Make a lighter version
For a lighter soup, replace part of the heavy cream with additional stock. The potatoes will still provide body, although the finished soup will be less rich and creamy.
Can you prepare the soup ahead of time?
Yes. Refrigerate the finished soup in a covered container for up to 3 days and reheat gently, stirring occasionally. Prepare the crostini and toppings just before serving so they retain their texture.