Combine flour, baking powder and salt in bowl. Set aside.
Place butter and sugar in another bowl. Beat at medium speed, scraping bowl often, until creamy. Add egg and vanilla; continue beating until well mixed. Add flour mixture; beat at low speed until well mixed.
Remove 1 1/2 cups dough. Add chocolate-hazelnut spread and ground hazelnuts to remaining dough; mix well. Divide each dough in half, making 4 portions.
Shape each portion of dough into rectangle. Roll each portion between 2 sheets of waxed paper into thin 10x6-inch rectangle. Remove top sheets of waxed paper.
Invert 1 chocolate rectangle on top of 1 plain dough rectangle; remove top sheet of waxed paper. Roll up tightly into log, starting at short end. Press in ends of roll to even. Wrap in waxed paper or plastic food wrap. Repeat with remaining portions of dough. Refrigerate 2 hours or until firm.
Heat oven to 375°F.
Cut logs into 1/4-inch slices with sharp knife. Place 1 inch apart onto ungreased cookie sheets. Bake 8-11 minutes or until set and lightly browned.
The chocolate-hazelnut spread used in this recipe is popular throughout Europe as a breakfast toast or afternoon snack topping. It can be found in the supermarket in the same section as peanut butter.