These Rugelach Bars came about as a result of the cookie for the book. This is just an easier, quicker version of this special cookie.
The pastry used for Rugelach Bars is easy to make and just as easy to roll out with no need to chill the dough first if made in the food processor. Two pieces of pastry sandwich a filling of jam, walnuts, cinnamon, and sugar. Any jam or any nut can be used. If the jam or preserves have pieces of fruit, it should be processed or blended to make it smooth.
Always on the lookout for a new flavor, I found this Red Plum jam recently. It worked well with the walnuts. However, as I said before, any flavor jam and any nut can be used for the filling. 
I hand chopped my walnuts into medium pieces. They shouldn't be too fine.
Cutting through the top pastry before baking makes it easier to cut after baking.
Rugelach Bar Pastry
2 ¼ cups all-purpose flour (315 grams or about 11 ounces)
½ teaspoon salt
1 cup unsalted butter, cold (225 grams, 8 ounces or 2 sticks)
8 ounces cream cheese, cold (225 grams or 1 package)
¼ cup sour cream (56 grams, about 2 ounces)
Processor Method
Place the flour and salt in the bowl of a processor. Pulse several times to mix.
Cut the butter and cream cheese into small pieces and place over the flour. 
Dollop the sour cream over.
Pulse until the pastry looks crumbly but sticks together when pressed. It should not form a ball.
Mixer Method
For this method, have the butter and cream cheese is barely softened. Place them, along with the sour cream, in the bowl of a mixer and beat until completely combined. Whisk together the flour and salt. Add to the creamed mixture and beat on low until crumbly.
Yield: About 820 grams
Assembly of Rugelach Bars
Preheat the oven to 375°F. Spray a 9x13 inch pan or a quarter sheet pan with a non-stick spray and set aside.
1 ¼ cups walnuts (140 grams or 5 ounces)
Pastry from above
1 cup red plum jam or any flavor jam*
1 ½ tablespoons granulated sugar
1 ½ teaspoons cinnamon
1 egg white, beaten
Sanding sugar as needed
*Whatever you like can be used. If using preserves, puree them in a processor or blender first.
Toast the walnuts (or whatever nut is used) for 7 to 10 minutes depending upon the size of the nuts. Cool completely. Chop them coarsely.
Pour the dough onto the work surface. 
Push it together and knead it several times to bring it together. 
If it is too soft to roll easily, refrigerate it to firm it up. Divide the dough in half about 410 grams or 14 ⅓ ounces. Roll one piece into a 9 ½ x 13 inch rectangle. Roll the second piece into a 9 x12 ½ inch piece. Refrigerate this piece.
Place the larger piece of dough into the bottom of the sprayed pan. Press the edges about ¼" up the sides of the pan.
Bake for 25 minutes until lightly browned and baked through. It may appear cracked but that is fine. Cool the crust.
I did not press my dough up the sides of the pan. It shrank slightly. Pressing it slightly up the sides of the pan should take care of the shrinkage.
Spread the jam over the crust.
Top with the toasted walnuts.
Combine the granulated sugar and cinnamon together and sprinkle over the nuts
Place the refrigerated piece of dough over the top. Let it warm up slightly. Press it gently over the nuts and make sure it adheres to the sides of the pan.
Whisk the egg white and brush the pastry lightly with the egg white. Sprinkle well with sanding sugar.
Cut through the top piece of dough only into 6 or 7 across and 4 down or whatever size you wish.
Bake for 35 to 40 minutes until golden brown. Cool about 10 minutes then go around the edges with a metal spatula to release them. Cut the bars following the marks on top. Clean the knife between cuts. Cool completely.
Yield: 24 to 28 bars.
Storage: Store at room temperature for up to a week in a covered tin.
If you like this recipe, you might want to try one of these:
Updated Lemon Bars
Hermit Bars
No Bake Peanut Butter Bars
Helen, again your timing is spot-on! How did you know I have a jar of IKEA lingonberry jam in the fridge that I need to use up? ;^)
Hi Mary - that sounds perfect.
I am looking forward to trying this recipe because it is a lot less work for Rugelach. Thank you.
I agree, Cheryl. So much easier and faster.
Hi, Helen. I would love to try these bars but all I have on hand is a bag of chopped hazlenuts. Do you think these would work instead of walnuts? Thanks you.
Hi Kathy, yes you can use whatever nuts you want. I mention that a couple of times. However, with hazelnuts because they are a hard nut, I would chop them finer.
How do you get the most hollowed out cream puffs for easier filling?
Hi Frank, go to my post on St. Honore. That is the pastry I have used for years - it is in my first book, The New Pastry Cook which is out of print. Sometime in the near future, I am going to post a comparative experiment on choux pastry.