In medium bowl, combine flour, baking powder and salt; set aside. In large bowl, beat butter and sugar with electric mixer until light and fluffy. Add egg and vanilla; Mix well Add flour mixture to butter mixture and beat until just combined.
On lightly floured surface, roll dough into a 12 inch by 9 inch rectangle about 1/4 inch thick. Spread jam evenly over dough; Sprinkle red sugar evenly over jam. Starting on long side, roll dough tightly to seal.
Cover with plastic wrap; Refrigerate at least two hours or overnight.
Preheat oven to 350°F. Cut dough into 1/4 in. slices; place on parchment lined cookie sheet.
Bake 10-13 minutes or until lightly browned. Cool on cookie sheet on cooling rack 5 minutes; Remove from sheet and cool completely.