These soft bars filled with raspberryjam are more virtuousthan many coffee-breaktreats. Applesauce givesthe cookies a cakelike texture; whole wheat flourand wheat bran add wholesome notes. Lemon zestbalances the sweetness ofthe berry jam.
Whisk together flours, bran, salt, andbaking soda in a medium bowl; set aside.Put brown sugar and zest in the bowl ofan electric mixer fitted with the paddle attachment; mix on medium speed until combined. Beat in butter until fluffy. Beatin egg until pale and smooth. Reduce speed to low. Mix in the flour mixture in3 batches, alternating with the applesauce. Divide dough in half; wrap in plastic. Refrigerate until firm, about 2 hours.
Preheat oven to 375 degrees. Roll out 1 pieceof dough between 2 lightly floured sheetsof parchment to a 9 1/2-by-11 1/2-inch rectangle, about 1/8 inch thick. If dough becomes too soft, refrigerate until firm.Remove top piece of parchment. Trimdough 1/2 inch on all sides. Transfer rectangle on parchment to a baking sheet.
Cut rectangle in half lengthwise.Spread 1/4 cup jam down half of eachlength, leaving a 1/2-inch border. Folddough over; pinch to seal. Refrigerateuntil firm, about 20 minutes. Repeat withremaining chilled dough and jam.
Cut crosswise into 1 1/2-inch-wide bars,but do not separate until after baking.Bake until golden brown, about 20 minutes. Let cool on sheet on a wire rack.
Bars can be stored in an airtight container at room temperature for up to 3 days.