In a medium bowl, whisk together the flour, baking powder, salt, cinnamon, and nutmeg; set aside.
In a large bowl, use an electric mixer on medium speed to mix together the sugar, butter, and orange zest, until mixture is light and fluffy, about 2 minutes.
Then, mix in the ricotta, and egg, until combined.
Add in the flour mixture and mix until just combined.
Fold in the chopped chocolate and pistachios.
Cover the cookie dough with plastic wrap and chill in the refrigerator for at least an hour or up to 24 hours.
When ready to bake, preheat oven to 350 degrees and line a baking sheet with parchment paper; set aside.
Remove cookie dough from refrigerator and use a cookie scoop to measure out about 1 ½ tablespoons of dough and roll into a ball.
Place on prepared baking leaving about 2 inches between each cookie.
Bake for 12-14 minutes or until the bottom of the cookie starts to brown slightly.
Cool on baking sheet for 5 minutes before removing to wire rack to cool completely.
Once cooled, drizzle melted chocolate over the top of the cookies. Alternatively you can dust the top of the cookies with the powdered sugar.
