1. Gather all ingredients and equipment needed.
2. Wash and rinse potatoes, then pat dry with a towel, peel, and hold in cold water. Using a grater, grate potatoes and place them in a bowl.
3. Squeeze excess water and pat dry with a towel and place in a bowl, add sliced yellow onions then season with salt and black pepper.
4. In a frying pan or skillet, on medium heat, add butter and evenly spread seasoned potatoes and onions, cook for 15 minutes, then using a spatula, gently release the bottom part from the pan. Then flip over to the other side and cook for another 15 minutes or until golden brown and crisp.
Note: use a chopping block to flip the potato pancake and then carefully slide it back onto the pan.
5. In a medium size bowl, or stand mixer, whisk the heavy whipping cream until medium stiffness. Then fold in horseradish, lemon juice, salt, and pepper.
6. To serve on a platter or individual plates, cut potato pancake in equal parts, serve with a dallop of horseradish cream, a dallop of lingonberry preserves and garnish will fresh dill.