1. Start with a highball glass—the taller, the better. If you’ve got one chilling in the freezer, bonus points. A cold glass keeps this coffee cocktail extra crips and refreshing from the first sip.

2. Measure out 2 oz of Atomic Black and pour it into your glass. It brings all the bold, roasted depth you’d get from fresh espresso, but with a smooth, boozy twist. Fill the glass to the top with ice to lock in that chill.

3. Top it off with tonic water—about 5 oz does the trick. The bitterness of the tonic balances beautifully with the sweetness of the liqueur, giving this espresso tonic recipe its signature edge. Stir gently to blend without dulling the bubbles.

4. Finish with a garnish of lemon. A twist adds brightness and aroma, while a wedge keeps things classic. Either way, that hit of citrus ties the whole drink together. Enjoy!