Makes: about 2 1/2 dozen at $2.76 per dozen.
1. Heat oven to 350 degrees F.
2. Combine flour, baking powder and salt in a medium-size bowl. Beat together on medium-high speed butter, sugar, egg white and rum extract in large bowl until light and fluffy, about 2 minutes. On low speed, gradually beat in flour mixture. Shape dough into disk and refrigerate in plastic wrap 30 minutes.
3. Roll out half of dough on floured surface to 1/4-inch thickness. Using 3-inch fluted round cutter, cut out cookies. Cut each in half. Place 1/2 inch apart on ungreased baking sheets. Reroll scraps; cut out.
4. Bake in 350 degrees F oven 10 to 12 minutes, until lightly browned around edges. Transfer to racks to cool. In small saucepan over low heat, melt chocolate, stirring. For each cookie, dip half a rounded edge into chocolate; let excess drip in pan. Repeat with other edge. Place on waxed paper until set. Repeat with remaining cookies.
5. Store airtight in cool place for up to 1 week.