Prepare cone molds for the horns: either metal ones or homemade cones rolled from parchment and foil.

Thaw the dough, cut it into long strips and wrap them around the molds.

Brush the tops with egg yolk and bake for 20 minutes at 190-200 °C. Let the finished horns cool and remove from the molds.

Put the sugar and water in a saucepan over the heat and cook the syrup to 120 °C - without a thermometer, bring it to a boil and cook for 5-7 minutes, until it thickens but still pours.

At the same time, whip the egg whites into a fluffy foam.

While continuing to whip the whites, pour in the syrup in a thin stream and keep whipping until the cream is thick and holds its shape.

Add the citric acid, whip once more and turn off the mixer.

Transfer the cream to a piping bag, fill the horns and dust with powdered sugar.