With buttered fingers, spread the marshmallow mixture evenly on the baking sheet and press lightly. Let cool for about 30 minutes. Spread about 375 ml (1 1/2 cups) hazelnut spread on the marshmallow mixture, then top with the strawberries. Roll from the shorter side, using the plastic wrap and place on a rectangular platter. Serve the same day. Store in the refrigerator if the room temperature seems too warm.