Preheat oven to 375°. Spray 2 large baking sheets with nonstick cooking spray; set aside.
For Cookies, in medium bowl, combine flour, baking powder and baking soda; set aside.
In large bowl, with electric mixer, beat Country Crock® Buttery Sticks with granulated sugar until light and fluffy. Beat in egg and vanilla. Alternately beat in sour cream and flour mixture just until blended. On prepared cookie sheets, drop dough using 1/4-cup measure or ice cream scoop, 3 inches apart. With moistened hands, flatten into 2-1/2 inch circles.
Bake 13 minutes or until edges are lightly golden. On wire rack, cool 2 minutes; remove from sheets and cool completely.
Meanwhile, for White Glaze, in small bowl, with wire whisk, combine confectioners sugar, 1/4 cup cream and vanilla. Cover and set aside.
For Chocolate Glaze, in small microwave-safe bowl, microwave chocolate, remaining 1/4 cup cream and Buttery Sticks at HIGH, 1 minute, stirring halfway thorough. Stir until smooth.
Spread 1/2 of each cookie with White Glaze, then let set about 10 minutes. Spread remaining 1/2 of each cookie with Chocolate Glaze, then let stand until hardened.