Preheat your oven to 350 degrees Fahrenheit and grab out a baking sheet.
In a large bowl use a hand mixer to cream together room temperature butter and sugar. Mix in the egg and vanilla extract.
Slowly, mix in flour, baking soda, baking powder, and salt.
Carefully fold in chopped pistachios and white chocolate chips until just combined.
Use a cookie scoop to grab an even portion of cookie dough and add to baking sheet. Do not flatten.
Bake for 12-13 minutes. Remove from the oven and sprinkle with flakey salt, if desired. Allow cookies to rest on baking sheet for 3-5 minutes then transfer to a cooling rack.
Notes
Store in an airtight container for up to 5 days.
Nutrition Facts are found via USDA's Food Data Central Database. Exact nutrition content may vary.