Preheat your oven to 375°F (190°C) and line baking sheets with parchment paper.
In a large bowl, mix the flour, baking soda, and cream of tartar. Set aside.
In the bowl of a stand mixer with the paddle attachment, cream together the butter, oil, granulated sugar, and confectioners' sugar on medium-high speed until light and fluffy, scraping the sides of the bowl as needed.
Reduce the speed to medium and add the eggs one at a time, mixing until just combined after each addition.
Add the vanilla and coffee grounds, mixing until combined.
Reduce the speed to low and add the flour mixture in three parts, scraping the sides of the bowl as needed.
Use a 2-tablespoon cookie scoop to place cookies on the prepared baking sheet, about 1 inch apart.
Bake for 8-10 minutes or until the cookie edges start to turn golden brown.
In a small bowl, whisk together confectioners' sugar and coffee until smooth for the glaze.
Drizzle the cookies with the coffee glaze and serve warm or cold.
Notes
For an extra coffee kick, you can add a pinch of instant espresso powder to the cookie dough.