01Preheat oven to 350 degrees F. Using a stand mixer on medium speed blend together butter and sugar until smooth (about 1-2 minutes) and creamy.
02Add the ricotta, vanilla and eggs, and mix well.
03Fold the lemon zest into the mixture.
04In a separate medium bowl, stir flour, baking powder and salt together until the ingredients are combined.
05Using stand mixer on low speed add the dry ingredients into the butter mixture in two halves to make sure dry ingredients are completely incorporated. Blend mixture until a soft, sticky dough forms and no dry ingredients are visible.
06With a spoon or a large cookie scoop (about 1 inch across) place dough onto greased baking sheets, placing cookies two inches apart. Bake for approximately 12-14 minutes until golden brown on top. Let the cookies cool to room temperature on a rack.
07For the frosting, using a whisk or mixer, in a medium bowl mix together the butter, powdered sugar, four tablespoons of milk and vanilla. Add up to eight tablespoons of milk if a thinner, glaze-like frosting is desired.
08If desired, mix in a few drops of food coloring. Frost cookies and top with holiday sprinkles.
09Store in an airtight container. To store longer than two days, refrigerate or freeze the cookies.