Sift together flour, baking powder and salt. Cream butter, sugar, sour cream, lemon peel and beat well. Add eggs, one at a time, and then milk. Gradually, add the sifted dry ingredients, scraping the bowl as necesary with a rubber spatula and beating only until thoroughly mixed. Divide dough into 2 halves. Wrap each atch with foil or plastic wrap and chill in refirgerator for 3 hours or longer. Do not place dough in freezer. Preheat oven to 400~. Place one batch of dough on lightly floured pastry cloth. Turn dough to flour all sides and roll out to desired thickness. For very large cookies, 1/4-inch. Cut the cookeis as you wish. Transfer cooies to ungreased cookie sheets. If cookies are large and thick, place at least 2 inches apart. Sprinkle the tops of the cookies generously with granulated sugar. Bake until the cookies are lightly browned. Large, thick cookies will need to bake for 10-12 minutes. Transfer cookies to racks for cooling. ----