Preheat the oven to 350 degrees.
In a large bowl or in the mixer, fitted with the paddle attachment, mix the butter, sugar and lemon zest until light and fluffy.
Add the vanilla, the egg and the ricotta. Mix until well incorporated.
In another bowl, whisk together all of the dry ingredients. Add the dry ingredients to the wet ingredients and stir just until incorporated. Don't over-mix the batter.
Form the cookies with a small ice cream scoop. Place them on a cookie sheet lined with parchment paper. Leave a couple of inches between the cookies.
Bake for 12 to 15 minutes or until the bottoms of the cookies are golden brown.
Whisk together 1 cup of icing sugar with 2 tbsp of fresh lemon juice. Allow the glaze to set for a couple of minutes before pouring onto the cookies. Test one cookie and adjust the glaze by adding more icing sugar or lemon juice to achieve your desired texture.
Top with sprinkles before the glaze dries.