Poppy seed cookies

Preheat oven to 375°F. In a small mixing bowl, cream together the butter and sugar until smooth. In a separate bowl, mix together the egg and vanilla. In another bowl, combine the flour, poppy seeds, and citrus zest. Add the butter mixture and egg mixture into the flour mixture and stir until light and combined. Spray a baking sheet with nonstick cooking spray. Drop small spoonfuls of batter onto the baking sheet. Bake for approximately 7 minutes or until lightly golden around the edges. Cool before serving.