2 tablespoons extra-virgin olive oil
3 pounds leeks, white and light green parts only, sliced thin
3/4 teaspoon salt, divided
1 bag Fifth Crow Farm potatoes, peeled or not peeled and diced
3 cups whatever kind of milk you prefer
2 cups reduced-sodium chicken or vegetable broth
3 tablespoons lemon juice
1/4 teaspoon ground white pepper, or to taste
Thinly sliced fresh chives for garnish
To prepare bisque: Heat oil in a Dutch oven over medium heat. Add leeks and 1/4 teaspoon salt. Cook, stirring occasionally, until very tender but not brown, 20 to 30 minutes. Adjust heat as necessary and add a bit of water if needed to prevent sticking. Set aside 1/3 cup of the leeks in a small bowl.
Add potatoes, milk and broth to the pot. Bring to a simmer (do not boil) and cook, stirring occasionally, until the potatoes are very tender, 10 to 15 minutes.
When the potatoes are tender, remove from the heat. Puree the soup with an immersion blender or in batches in a regular blender. (Use caution when pureeing hot liquids.) Season with the remaining 1/2 teaspoon salt, lemon juice and white pepper. Divide among 8 soup bowls. Garnish with chives, if desired.