Preheat the oven to 350°.
With a mixer on medium speed, cream the sugar and butter.
Increase speed to high and beat for 5 minutes. You want it very light and fluffy.
Reduce to medium speed and beat in the ricotta cheese, vanilla extract, and eggs until well combined.
Reduce to the lowest speed and add the flour, baking powder, and salt. Mix it until a dough forms.
Drop dough by tablespoons, 2 inches apart, onto an ungreased cookie sheet.
Bake about 15 minutes, or until the cookies are very lightly golden. The cookies will be slightly soft, but they firm as they cool.
Cool in the pan on a wire rack for a few minutes, then remove them to the wire rack to continue cooling.
Frost the tops with the GLAZE: Stir the confectioner's sugar and the milk to get a thin glaze.
Store the cookies covered at room temperature.