Beat the whipped cream with the cream stabilizer using a whisk for 3-5 min until stiff peaks form. Stir in the mint syrup until fully combined. Refrigerate for 10 min.
While the cream chills, prepare 4 cups of fresh coffee. Pour the coffee into 4 tall cups. Pour a quarter of the mint cream into each cup without stirring. Dust each serving with a pinch of cocoa powder and serve immediately.