Cream Cheese Dough: 4 cup(s) all-purpose flour, 1 teaspoon baking powder, 1 teaspoon salt, 1 cup (2 sticks) butter (no substitutions), softened, 6 ounce(s) cream cheese, softened, 1 cup granulated sugar, 1 cup (packed) brown sugar, 2 large eggs, 1 tablespoon(s) vanilla extract
Chocolate Filling: 1 can (14-ounce) sweetened condensed milk, 8 ounce(s) bittersweet or semisweet chocolate, cut up, 1 cup walnuts, coarsely chopped
Confectioners’ sugar for sprinkling
1. Prepare Cream Cheese Dough: In medium bowl, combine flour, baking powder, and salt. In large bowl, with mixer on medium speed, beat butter and cream cheese until well blended. Gradually add sugars and beat 3 minutes or until light and creamy, occasionally scraping bowl with rubber spatula. Add eggs, 1 at a time, beating well after each addition. Beat in vanilla. Reduce speed to low; gradually beat in flour mixture just until blended, occasionally scraping bowl. Place 1/4 dough on sheet of plastic wrap. Repeat to make 4 more. Wrap each with plastic wrap and refrigerate overnight.
2. When ready to roll out dough, prepare Chocolate Filling: In 2-quart saucepan, heat sweetened condensed milk and chocolate over medium heat just until chocolate melts, stirring frequently. Remove saucepan from heat; stir in walnuts. Cool filling to room temperature, about 30 minutes.
3. Preheat oven to 350 degrees F. Grease 2 large cookie sheets. 4. Remove 1 piece of dough from refrigerator. On lightly floured 16-inch sheet of waxed paper, with floured rolling pin, roll dough into 10" by 6" rectangle. Spread heaping 1/4 filling lengthwise down center of rectangle. Starting from a long side and using waxed paper to help lift dough, fold 1 side of dough lengthwise over filling, then remaining side over dough (dough should overlap).
4. Pick up waxed paper and flip cookie log onto 1 side of prepared cookie sheet, seam side down. Repeat with another piece of dough and filling. Flip second log parallel to first log, leaving about 2 inches between logs. 6. Bake logs 20 to 22 minutes or until edges are lightly golden. Cool logs on cookie sheet 2 minutes, then transfer to wire rack to cool completely. While logs bake, repeat with remaining dough and filling.
5. Wrap each cooled log separately with foil or plastic wrap, and store in tightly covered containers at room temperature up to 2 weeks or in freezer up to 3 months. 8. To serve, sprinkle logs with confectioners’ sugar. Cut each log crosswise on the diagonal into 12 slices. (If logs are frozen, thaw completely at room temperature before sprinkling with sugar and slicing.)