Preheat oven to 350°F (175°C) and line baking tray with parchment.
Whisk flaxseed with water and let sit until it thickens and overachieves.
In a bowl, cream butter, brown sugar, and white sugar until it looks fluffy and fabulous.
Add vanilla and flax egg to the butter-sugar mix and stir like you mean it.
In another bowl, mix flour, salt, baking soda, and ground coffee—because dry ingredients deserve their own drama.
Combine wet and dry ingredients into a thick, irresistible dough.
Fold in those chocolate chips like a classy rebel.
Scoop dough onto baking tray in heaping tablespoon-sized mounds.
Bake for 11–12 minutes or until edges are golden and centers still look slightly underbaked.
Cool on tray for 5 minutes, then transfer to a rack—if you can wait that long.