Whisk together flour, sugar, baking powder, baking soda and salt for 30 seconds. Make a well in center of flour mixture and set aside. In a separate large mixing bowl, whisk together milk, ricotta, eggs and vanilla until well blended. Then, whisk lemon zest with lemon juice and add to milk mixture along with melted butter and blend until combined (it will curdle a little, that's fine, but you'll want to hurry and pour it into the dry mixture). Pour into flour mixture and whisk just to combined (batter should be slightly lumpy).
Put ingredients not saucepan over high heat, bring to boil stirring frequently. Reduce heat, cover & cook about 15 or 20 till rice is soft. (May need to stir after 10.)