These Vietnamese coffee shortbread cookies are built on a buttery shortbread base, upgraded with condensed milk and a generous dose of instant espresso for that signature bitter-sweet taste.
Cream the butter - Add softened butter, vanilla, condensed milk, sugar and salt to a stand mixer bowl fitted with the paddle attachment. Beat on medium speed until the mixture is thoroughly incorporated and creamy.
8 oz unsalted butter, ⅔ cup granulated sugar, 3 tablespoon sweetened condensed milk, ½ teaspoon pure vanilla extract, ¼ teaspoon kosher salt
Incorporate dry ingredients - Sift the flour, cornstarch and instant espresso powder directly into the creamed butter using a fine mesh sieve, stir to combine. Increase the mixer speed and beat until no trace of flour remains and the dough is formed.
Form the logs - Place a long piece of plastic wrap flat on the countertop. Divide cookie dough into 2 equal portions. Roll each portion on top of the plastic wrap into a log about 6” in length. Wrap it up with the plastic and refrigerate for at least 1 hour. You don’t need additional flour for rolling but you can use some flour if necessary. I usually refrigerate shortbread dough overnight to prep ahead.
Slice the cookies - Use a sharp knife to slice each cookie dough log into 12 cookies about ½” thick. Rewrap in the same plastic and place them into the freezer while the oven preheats, about 15 minutes. Or you can freeze for longer storage at this point.
Preheat the oven - Set the oven rack in the middle of the oven and preheat to 350°F.
Bake - Place 12 cookies on a large lined baking sheet, about 2 inches apart. Sprinkle granulated sugar on top. Bake 1 batch at a time for 20 minutes, until the outer edges of the cookies are golden.
Extra granulated sugar for topping
Cool - Remove the baking sheet from the oven, but allow the cookies to sit on the baking sheet to finish baking from the residual heat for 5-10 minutes before removing them to a wire rack to cool completely.
Make the glaze - When the cookies are completely cool and you’re ready to decorate, make the glaze by adding hot water to instant espresso powder and mix to dissolve. Then add condensed milk, powdered sugar and salt and whisk until smooth.
2 teaspoon instant espresso powder, 2 teaspoon hot water, 2 tablespoon sweetened condensed milk, 1 cup powdered sugar, A few pinches of kosher salt
Glaze the cookies - Transfer the glaze to a piping bag or a ziploc back and snip the corner to create a small opening. Drizzle coffee glaze on top of the cooled cookies. Let the glaze dry completely before storage.
Notes
Storing baked cookies: once the glaze is completely dry, you can store your coffee shortbread cookies in an airtight container at room temp for up to a week.
Storing cookie dough: cookie dough can be kept refrigerated for 3-4 days before baking to prep ahead. Or slice and freeze for 3-6 months.
Baking frozen dough: no need to thaw frozen cookie dough, you can bake directly from the freezer.