Method
1. Add boiling water, let it sit until the mug feels warm, then empty it
2. Add brown sugar and water to a clean small glass bowl
3. Stir with teaspoon until dissolved then set aside
4. Add hot coffee, irish whiskey and water to the mug
5. Transfer sugar mixture to mug
6. Stir with teaspoon until combined
7. Add single cream and orange to a clean jar
8. Shake vigorously until thickened
9. Pour the thickened cream gently over the back of a spoon, so it floats on top
10. Sprinkle with nutmeg