Brown the butter. Heat butter over medium heat until it fully melts. Lower the heat to medium low and let it cook until golden brown and brown bits start to appear at the bottom of the pan. Pour butter into a large mixing bowl and set aside. Let it cool for 10 minutes. If it’s too hot when you use it, your cookie dough will be greasy.
Combine flour, baking soda, salt, espresso powder, and Vietnamese cinnamon in a separate bowl. Mix and set aside.
Once butter has cooled, add granulated sugar, dark brown sugar, and light dark brown sugar to the bowl. Mix.
Add the room temperature egg to the bowl and mix until a smooth, brown texture. See image above for reference.
Add the vanilla extract and mix.
Add the dry ingredients from step 2 and gently fold into the wet ingredients. Be careful not to overmix. I would stop when there’s a little bit of flour left because you will need to mix in the chocolate chips.
Add the chocolate chips and mix until incorporated.
Let the cookie dough rest in the fridge for 45 minutes. You need to let the butter get cold enough so the butter won’t melt too fast which will create flat cookies.
Preheat the oven to 350 degrees F (177 degrees C).
Prepare 2 baking sheets by covering them with parchment paper.
Use a 2 tablespoon (medium sized) cookie scoop to scoop your cookie dough onto the prepared baking sheet. Make sure there are 2 inches of space between each cookie.
Bake for 14-16 minutes until the edges are light brown.
Rest for 10 minutes on the baking sheet and then another 10 minutes on the cooling rack before serving.