Measure the coffee into a saucepan. Pour in the boiling water and stir well. Return to the heat for about 1 minute until the coffee just comes to the boil. Draw off the heat, cover and leave to infuse for 6–8 minutes.
Strain through muslin or a fine strainer and return the coffee to the pan. Add the sugar. Stir over low heat to dissolve the sugar, then boil without stirring for 2 minutes. Remove from the heat and allow to cool. Pour into a bottle, cover and store in a cool place.
To use, measure