• Fill a large bowl with cold water. Add leeks. Use your hands to swirl them around and let the dirt and debris fall to the ground. Remove the leeks from the water and dry them on paper towels. Set two tablespoons aside for later.
• Add 3 tablespoons butter to a large heavy bottomed pot or dutch oven. Turn the heat on medium-high. Let the butter melt, and when it starts to brown, swirl the pot. When the butter smells nutty and is a deep golden brown, turn the heat down to medium.
• Add the leeks and shallots to the butter along with 1/2 teaspoon salt. You don’t want them to get too brown, so you may have to teeter between medium and medium low depending on your stove. Let the veggies sweat for 3-4 minutes until soft. Add garlic. Cook for 1 minute. Add wine. Bring to a boil and reduce to a simmer. Simmer until slightly reduced, about 1-2 minutes. Add potatoes and another 1/4 teaspoon salt. Coat in the leeks and butter and cook another 1-2 minutes until the garlic is fragrant.
• Stir in the chicken stock and another 1/4 teaspoon salt. Bring to a boil and reduce to a simmer. Cover and simmer until the potatoes are fork-tender, about 12-15 minutes.
• Carefully transfer the hot soup to a blender. Add another 1/4 teaspoon salt. Cover with the lid and put a towel on top to prevent any spillage. Blend until smooth.
• Add the soup back to the pot and add in cream. Simmer another 2-3 minutes. Add vinegar. Stir to combine. Season to taste with salt and pepper.
• Ladle soup into bowls. Sprinkle with leeks and pine nuts. Drizzle with extra butter.

Brown Butter Pine Nuts

• While the soup simmers, make the brown butter pine nuts. Add the remainig 3 tablespoons butter to small skillet. Turn the heat on medium-high. Let the butter melt, and when it starts to brown, swirl the pot. When the butter smells nutty and is a deep golden brown, throw in the pine nuts and leeks. Cook for 1-2 minutes until the leeks are crispy and the nuts are slightly brown. Turn the heat off and set aside.