1. Brew the ground coffee in a jug or cafetiere with the boiling water and leave for 5 minutes. Strain into a clean jug and stir in the 4tsp Tate & Lyle Demerara sugar. Leave to cool, then chill.
2. Stir the Irish whiskey into the chilled coffee and pour into 2 glasses.
3. Whip the cream in a chilled bowl until it holds its shape, then spoon it on top of the drinks. Sprinkle with a little extra Demerara sugar, then serve.