(Dairy with butter or Pareve with margarine or oil.)
1. Coat a large bowl with cooking spray or olive oil and set aside.
2. Heat rum in the microwave or on stovetop until hot. Pour over raisins to submerge them completely. Let stand about 10 minutes. Drain and discard the rum and pat the raisins dry. Set aside.
3. Dissolve the yeast and the warm water in a large bowl, about five minutes. Mix in the sugar, three whole eggs and the one egg white, butter and vanilla. Stir in 2½ cups of the flour and the salt, and combine well. Then add 2½ more cups of flour and mix well. Add additional flour as needed to form a cohesive dough.
4. Transfer the dough to a lightly floured surface and knead for about 10 minutes until smooth and elastic. Press the dough into a large thick disk, and insert a handful of the raisins, spaced apart. Fold the dough over the raisins and flatten again; continue inserting raisins this way until all are incorporated and well distributed.
5. Place the dough in the oiled bowl, then lift out, turn over, and place it (oiled side up) back in the bowl. Cover with plastic wrap and set in a warm place to rise until doubled, about 1½ to 2 hours.
6. Uncover the dough and press down on the middle to deflate. Cover and let rest for a few minutes.
7. Line a baking sheet with parchment paper and set aside. Prepare the filling by stirring together the brown sugar and cinnamon. In a separate bowl, combine the vanilla extract and the melted butter or margarine.
8. Divide the dough in half. Return one half to the bowl and cover. Place the other half on a lightly floured surface. Roll out to a large rectangle, about 20 inches long by 9 to 10 inches wide. Brush a thin layer of the butter over the dough. Then sprinkle with half the brown sugar mixture.
9. Starting at one long edge of the dough, roll it (jelly-roll style) gently but firmly to the other edge. Press the seam and ends to seal. Gently pull and roll this log until it is about 24 inches long, keeping the original thickness on one end and gradually narrowing the other end. Twine the narrow end around the larger end to make a large pinwheel. Press the loose end to seal. Gently press down on the top of the entire loaf to level it.
10. Transfer to prepared baking sheet. Repeat with remaining dough. Prepare the egg wash by lightly beating the reserved egg yolk, a pinch of salt, and 1 teaspoon cold water to combine. Brush on shaped loaves. Gently cover the loaves with oiled plastic wrap and let rise about 45 minutes, until nearly doubled. Halfway through the rise, preheat the oven to 375 degrees.
11. Bake for 20 minutes, and then reduce heat to 350 degrees. Bake another 15 to 18 minutes, until loaf sounds hollow when tapped (the interior should be between 185 and 190 degrees). Some of the sugar mixture might seep out and create a sweet undercrust, which I consider ideal. Serve the same day or freeze.
Recipe reprinted with permission from Meatballs and Matzah Balls: Recipes and Reflections from a Jewish and Italian Life