Sift first 4 ingredients into a medium bowl. Mix in pepper. Using electric mixer, cream butter in orange peel and vanilla and almond extracts. Mix in walnuts. Add dry ingredients and mix just until blended. Cover dough with plastic wrap and refrigerate until well chilled. Preheat oven to 180ºC . Line two baking sheets with parchment paper. Divide dough into 3 pieces. Using lightly floured hands, roll each piece into 4 cm diameter log on lightly floured surface. Arrange 2 logs on one sheet, spacing 13 cm apart. Arrange third log on second sheet. Bake until logs are light brown, about 20 mins. Cool slightly on pan. Cut logs crosswise on diagonal into 2 cm wide slices. Turn cut side down on baking sheet. Bake until golden brown, about 15 mins. Transfer to racks and cool thoroughly. Store in airtight container.