Boil the potatoes in salted water for about 20 minutes. Peel and finely chop the egg. Cut the salmon into fine cubes. Peel and finely dice the shallot.
Mix the quark, crème fraiche and milk together. Fold in the egg, cubed salmon, cubed shallot and dill. Season with salt and pepper. Serve with the (possibly already peeled) potatoes.