Preheat your oven to 400°F (200°C). Take a whole bulb of garlic, slice off the top, and drizzle with olive oil. Wrap it in aluminum foil and place it on a baking sheet. Roast for 30–40 minutes until the garlic is soft and golden brown.

In a large pot, pour in your chicken stock and bring it to a gentle boil over medium heat. Add in dried sage and a pinch of salt. Once bubbling, reduce the heat and let it simmer.

After roasting, carefully unwrap the garlic and allow it to cool slightly. Squeeze the soft garlic cloves into a bowl and mash them into a smooth paste.

In a small bowl, combine the room-temperature egg yolk with Dijon mustard. Whisk until smooth, then slowly drizzle in your olive oil while whisking to create a creamy emulsion.

Gradually incorporate the mashed garlic into the stock, whisking continuously. Temper the egg emulsion with hot stock before pouring it back into the pot.

Ladle your soup into warm bowls and serve hot. Pair it with crusty French bread or sprinkle with crispy bacon or fresh herbs.