Heat first 4 ingredients in a saucepan, stirring occasionally, until butter melts. Cool to 105° to 115°.
Combine yeast and warm water in a large mixing bowl; let stand 5 minutes. Stir in sour cream mixture and eggs; gradually stir in flour (dough will be soft). Cover and chill at least 8 hours.
Divide dough into fourths. Turn out each portion onto a heavily floured surface, and knead 4 or 5 times.
Roll each portion into a 12- x 8-inch rectangle, and spread each rectangle with one-fourth of Cream Cheese Filling, leaving a 1-inch border around edges. Carefully roll up, starting at a long side; press seam, and fold ends under to seal. Place, seam side down, on lightly greased baking sheets. Cut 6 equally spaced Xs across top of each loaf; cover and let rise in a warm place (85°), free from drafts, about 1 hour or until doubled in bulk.
Bake at 375° for 15 to 20 minutes or until browned. Drizzle warm loaves with Powdered Sugar Glaze.