In the bowl of an electric mixer, cream margarine and sugars until light and fluffy. Add eggs, lemon juice, flour, and baking powder, and mix for 3-5 minutes, until the flour is fully incorporated.
Preheat oven to 350°F. Line baking sheets with parchment paper.
Roll dough out onto a floured surface and cut into desired shapes. Place cookies on prepared baking sheets. Bake for 8-10 minutes (remove from oven before the edges start to brown). Let cool, then remove cookies from baking sheet.