Beat the sugar and egg yolks together until light and thick. In a separate bowl, cream the butter until smooth, then add the beaten sugar and egg yolks, mixing well.
Press the tvorog through a fine sieve, then mix it in well with the butter mixture, beating until the mixture is completely smooth. Slit the vanilla bean lengthwise and scrape the seeds out into the cheese mixture. Stir in the cream.
Line a 3-quart paskha mold or large clay flowerpot with cheesecloth. Pour the cheese mixture into the mold, folding the cheesecloth over the top. Set the mold in a bowl in the refrigerator. Place a saucer on top of the mold, and set several heavy cans on it to weight the cheese mixture down and force the liquid out through the drainage hole in the bottom of the mold or flowerpot.
Let the paskha drip overnight in the refrigerator, until all excess liquid has drained out. Unmold.
Decorate the sides of the paskha with the letters XB in currants or nuts. Serve chilled.
Recipe by Darra Goldstein at https://darragoldstein.com/maria-nikolavenas-pashka/