From the Essential Pépin tv series, Episode 120: Souper Soups For Supper
There are almost endless possibilities for variation here. Potatoes are my favorite thickening agent for garlic soup, but it can also be thickened with a roux of flour and butter or with bread, the traditional choice in the South of France, where this dish is a specialty. Onions and scallions can be used instead of leeks, although the soup won’t have the same subtle taste. If you use the leeks, include most of the green leaves.
Poultry or meat stock gives the soup more body and flavor, although it’s good made with water. I have purposely kept the soup simple, but for a party, you could enrich it by adding a cup of light cream at the last minute. —Jacques Pépin
Serves 6 to 8
1/4 cup olive oil
2 medium leeks, trimmed (leaving most of the green), split, washed, and sliced
12–15 garlic cloves
7 cups homemade chicken stock (see recipe below) or low-salt canned chicken broth
2 pounds potatoes, peeled and cut into 1-inch cubes (about 4 cups)
1 teaspoon salt, or to taste
2 cups cubed (1/2-inch) firm-textured white bread
2 tablespoons unsalted butter