Peel and dice about 2 pounds of starchy potatoes into small cubes. Rinse and chop roughly 3.5 ounces of fresh dill, setting aside a bit for garnishing.

In a large pot, heat 2 tablespoons of cooking oil or butter over medium heat. Add finely chopped onion and sauté for about 3-4 minutes until translucent.

Introduce the chopped potatoes to the pot, stir gently, then pour in about 6 cups of stock. Bring to a boil, then reduce heat and simmer uncovered for about 20-25 minutes.

Blend the soup with an immersion blender until creamy. For a chunkier texture, blend only half.

Stir in the chopped dill and 1 cup of heavy cream. Heat through on low for another 5 minutes.

Ladle the warm soup into bowls, garnishing with reserved dill. Serve immediately.