Preheat oven to 350 degrees Fahrenheit. In a medium bowl, stir together flour, baking soda, and salt.
In the bowl for a stand mixer (or using a hand mixer) beat together butter and sugars until it’s light and fluffy on medium speed, about 3-4 minutes.
Add in eggs one at a time and stir. Then add in orange liquor.
Add in dry ingredients and stir until just combined. Then stir in oats, chocolate, and peeled pistachios.
Spoon cookie dough onto baking sheets (I like to line mine with parchment paper). The cookies should be heaping tablespoons. You should be able to get 12 on a normal baking sheet, but be sure to leave about 2 inches between cookies.
Bake cookies for 8-10 minutes at 350 degrees Fahrenheit until they are lightly browned around the edges.
Remove cookies and let cool for at least 10 minutes before eating.