Espresso Martini (no sugar & low-calorie)

Name: Espresso Martini (no sugar & low-calorie)
Prep time: 5 min
Cook time: 5 min
Total time: 5 min
Yield: 1 cocktail
Cuisine: Cocktail
Ingredients: 1.25 cl Sugar-Free Sweetener; 4.5 cl Vodka; 1 ⁄2 pinch Salt; 4.5 cl Espresso Coffee