Start by melting the butter over medium heat. Continue cooking until it turns golden brown and smells nutty. This step adds deep flavor and richness. Remove from heat and let it cool before using.
In a separate bowl, whisk together flour, baking soda, salt, espresso powder, and Vietnamese cinnamon. Mixing these first ensures even distribution
In another bowl, combine cooled brown butter with granulated sugar, dark brown sugar, and light brown sugar. Beat until smooth and creamy. Add the egg and vanilla extract, mixing until fully incorporated.
Gradually fold the dry ingredients into the wet mixture. Stir gently until just combined. Add chocolate chips and mix evenly. Cover the dough and chill for about 45 minutes to help the cookies hold their shape while baking.
Preheat the oven to 350°F (177°C). Line baking sheets with parchment paper. Scoop dough into evenly sized balls and place them apart. Bake for 14–16 minutes until edges are golden. Let cool before serving.