Preheat oven to 350
In a bowl, cream together butter and sugars.
Add vanilla
Add eggs, one at a time, beating well after each addition
In a separate bowl, sift together flour, baking soda and salt
Alternately mix in flour mixture and ricotta cheese to butter mixture. Start and end with flour mixture.
Drop by teaspoonfuls on a cookie sheet. Bake for 10-15 minutes. Cool completely on a wire rack