Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: see manufacturer). Unroll the tarte flambée dough together with the baking paper on a baking tray. Mix sour cream and horseradish. Season with salt and pepper. Spread the dough with it. Bake in a hot oven for 12-15 minutes.
Meanwhile, wash the dill, shake dry and cut the flags finely. Take the tarte flambée out of the oven, cover with salmon and half of the dill. Continue baking at the same temperature for 2-3 minutes. Remove. Serve with caviar and the rest dill.