Dissolve yeast in lukewarm milk: add melted butter. Sift flour with the salt. Add milk to flour. Knead until smooth, allow to rise in covered bowl in a warm place, about 1 hour. Soak pears and prunes overnight in cold water. Cook in the soaking water about 20 minutes, drain off water and put fruit through a meat grinder. Add coarsely chopped nuts to the fruit mixture. Soak raisins in kirsch: add to the mixture, along with sugar and spices. Knead mixture into one-third of the dough, and shape into two narrow loaves. Roll out remaining dough, cut into two rectangles, and wrap around the fruit loaves. Fold the ends under and place on metal baking sheet with the seam on the bottom. Prick several times with a fork. Allow to rise in a warm place for one hour. Brush with egg yolk and bake in a pre-heated 340F oven for about one hour. (From CULINARY EXCURSIONS THROUGH SWITZERLAND, Sigloch Editions, D-7118 Kuenzelsau, Germany, 1985,1988. No ISBN. A translation of KULINARISCHE STREIFZUEGE IM SCHWEIZ, by the same publisher. These people specialize in German regional cookbooks: other titles (unfortunately not translated) include "culinary excursions through" Swabia, Bavaria, Hesse, the Rheinland, Friesland, Baden, Franconia, Pfalz, Westphalia and Niedersachsen.)