For pudding, in a heavy medium saucepan, combine sugar, cocoa powder, cornstarch and espresso powder. Whisk in the water and evaporated milk. Cook and stir over medium heat until thickened and bubbly; cook and stir 2 minutes more. Remove from heat. Place egg whites in a medium bowl; gradually whisk about 1 cup of the hot mixture into the egg whites. Slowly pour mixture back into hot mixture in saucepan, whisking constantly. Cook, stirring constantly, over medium-low heat about 2 minutes or until slightly thickened; whisk in butter, coffee extract and vanilla. Transfer to a medium bowl. Cover surface with plastic wrap. Chill at least 4 hours or up to 24 hours.
Fold crushed espresso beans into the whipped topping.
Using eight 6-ounce clear dessert cups or glasses, spoon 3 tablespoons of the pudding into each cup; spoon 2 tablespoons of the whipped topping mixture over pudding in each cup. Repeat layers. Garnish with mint leaves. If desired, top with whole chocolate-covered espresso beans.
Tip: If using a sugar substitute, choose from Splenda® Sugar Blend or C&H Light® Sugar Blend. Follow package directions to use product amount equivalent to ½ cup sugar. Nutrition per Serving with Substitute: same as below, except 141 calories, 22 g carbohydrates, 13 g total sugar.