This is the real thing from Vienna. Topfen, called Quark in Germany, is an unsalted curd cheese that’s used a lot in sweet and savoury dishes in Austria. You could use cream cheese or ricotta as a replacement.
60 grs butter at room temperature
50 grs sugar
2 eggs, separated into yolks and eggs whites
250 grs unsalted fine curd cheese
125 ml sour cream
finely grated zest of 1 organic lemon
40 grs raisins
additional butter to brush the outside of the strudel
1 package of filo pastry
Preheat the oven to 180 degrees Celsius. Prepare the filling: Whisk the egg whites until very stiff. In a separate bowl, whisk the butter until soft, then add sugar, yolks, strained curd cheese, sour cream, zest and raisins. Mix well, then carefully fold the beaten egg whites into the rest of the mass.
On your counter-top, place a slightly moist kitchen cloth, then open the package of filo pastry (it dries out in minutes, so wait until the last minute). On the towel, place one sheet of pastry on top of a second sheet. Spread the filling on one fifth of the pastry sheets, leaving space on the sides around it. Then fold in the sides and start to roll up the strudel with the help of the table cloth underneath it. Place on a greased baking tray, brush with melted butter and bake for 30-40 minutes until golden
Dust with icing sugar and serve warm. For added richness, the strudel can be served with hot home-made vanilla custard.
Source: Hess, Wiener Küche