- 50 g butter
- 50 g plain flour
- 20 ml dark rum
- 250 ml milk
- 50 g caster sugar
Heat the butter in a pan, then add the flour and mix.
Add the milk a little at a time, whisking it in fully between additions; keep stirring the sauce until it thickens.
Add the rum and sugar, whisk them in, then remove the sauce from the heat.