Start by heating 4 cups of chicken stock in a Dutch oven over medium heat. Add 4 sprigs of fresh sage, stirring gently.

Peel and prepare 10 cloves of garlic. Boil them in a small pot for 3-4 minutes until soft.

Stir the smashed garlic into the simmering chicken stock and let it simmer for about 10 minutes.

In a small jar, combine 1 egg yolk, 1 tablespoon of Dijon mustard, and a pinch of salt, then blend while drizzling in 1 cup of olive oil.

Strain the soup through a fine mesh strainer if desired for a velvety texture.

Whisk in a few spoonfuls of the hot soup into the mayonnaise, then pour it back into the pot of soup while stirring gently.

Ladle the soup into bowls and garnish with croutons, a drizzle of olive oil, and parsley.