Chill your mixing bowl and beaters in the refrigerator for about 10 minutes. Pour the heavy cream into the chilled bowl and whip until stiff peaks form, about 3-5 minutes. Transfer to a separate bowl.

In the same bowl, add the cream cheese and beat until softened, about 1-2 minutes. Gradually add powdered sugar while mixing until light and fluffy.

Stir the instant coffee granules into the cream cheese mixture and continue mixing for about 1 minute until fully dissolved.

Gently fold in one-third of the whipped cream into the coffee cream cheese mixture, then fold in the remaining whipped cream until no white streaks remain.

Spoon or pipe the mousse into serving bowls or glasses. Garnish as desired and serve immediately or refrigerate for later.