Heat the butter in a pan. Sauté the carrots for approx. 5 mins. Mix in the dates and all the other ingredients up to and including the salt, leave to cool.
Carefully unfold the pastry sheets, brush with a little butter and stack them on top of each other on a cloth. Spread the filling over the bottom third, leaving a border of approx. 3 cm along the sides, fold the pastry ends inwards. Loosely roll up the strudel, using the tea towel to help you. Place it seam-side down on a baking tray lined with baking paper, brush with a little butter.
Approx. 25 mins. in the lower half of an oven preheated to 200°C. Brush the strudel with the remaining butter several times during baking. Remove from the oven, allow the strudel to cool slightly on a rack, dust with icing sugar.