Asparagus Soup with Poached Egg Croutons and Black Truffle Flakes

This is one of my recipes for asparagus soup.
It's simply pureéd till it’s silky smooth,
the rest is just delicious herbed and seasonings.
A soft poached egg in the middle of the dish.
It’s sure to make your guests very happy.

Ingredients:
2 tablespoons extra-virgin olive oil
1 tablespoon butter
1 medium onion, finely sliced
1 garlic clove, chopped
salt to taste
1 pound asparagus (separate the stems and slice the rest)
3 fingerling potatoes, peeled and sliced
2 sprigs tarragon
1 quarts chicken stock
1-2 tablespoons creme fraiche
Garnishes:
Croutons
Black truffle (optional)
Truffle oil
Tarragon leaves
4 eggs
3 tablespoons white vinegar

Directions:
For the asparagus soup:
Heat the oil and butter in a medium pot over medium heat,
add the onion and 1/2 teaspoon salt.
Cook gently for five minutes until the onion has softened.
Add the garlic and tarragon, stir together for a minute,
then add the potatoes, asparagus stems and chicken broth.
Bring to a boil, reduce the heat, cover and simmer for 10 minutes.
Remove and discard the asparagus stems and add the
chopped asparagus and simmer until soft, about 5 minutes.
Add the creme fraiche and blend the soup until silky smooth,
strain and cool rapidly over an ice bath.
To serve:
Boil water in a wide stockpot and add the vinegar.
When it comes to a simmer, break the eggs one by one
and poach them for 3 minutes. Remove with a slotted spoon.
Meanwhile heat the asparagus soup.
Pour the soup in four soup bowls,
top each one with a poached egg.
Add croutons, chopped truffle (if using),
a drizzle of truffle oil, and tarragon leaves.
Serve immediately.