Oxford Night Caps by Richard Cook (1860, p.29) — Oxford 1860
| 8 whole | egg yolk — egg yolks | base |
| 0.5 pint | rum — Optional; the text says it is sometimes added. | base |
| cinnamon — A piece. | other | |
| 1 whole | nutmeg — Grated. | other |
| 1 bottle | white wine — Boiled, then softened with one glass of cold white wine. | other |
| 1 glass | white wine — cold white wine | other |
| sugar — refined sugar | sweetener | |
| sugar — lemon-scented loaf sugar | sweetener |
- Beat the yolks of eight eggs with pulverised sugar and grated nutmeg.
- Put the lemon-scented sugar, a piece of cinnamon, and the bottle of white wine into a clean saucepan and bring it to the boil.
- Take the wine off the fire, pour in one glass of cold white wine, and gradually pour the mixture from a spouted jug into the egg yolks while stirring constantly.
- Sweeten further if needed, then throw the mixture rapidly from one vessel to another until a fine white froth is obtained.
- If desired, add half a pint of rum and serve quite hot.
Cook presents Rum Booze and its descendants as drinks with affinity to the old sack-posset line.
The temperature control and vessel-to-vessel throwing are both essential to avoid curdling and generate froth.