Mix flour, baking powder and salt well in a large mixing bowl, set aside.
In a separate bowl whisk egg, lemon zest, lemon extract and vanilla extract, set aside.
Place butter, ricotta and sugar into the bowl of an electric mixer. With the whisk attachment, whip together until smooth.
Add mixture to the bowl and continue mixing.
Turn mixer to low, and slowly add the flour mixture, a little at a time to the bowl. Continue mixing until blended. Scrape sides as needed.
Place the cookie dough in a bowl and cover. Place in the refrigerator for at least an hour to chill.
When ready to bake, heat oven to 350 degrees.
Place about a rounded tablespoon cookie dough on a cookie sheet lined with parchment paper. Make sure cookies are at least 2 inches apart.
Bake for 15-17 minutes. Let cool completely.
Frost cookies and top with chopped pistachios and lemon zest.