Mixers

Butter

Butter is churned cream, at least 80% milk fat under the retained Regulation (EU) 1308/2013. In our Hot Buttered Rum, 30g of unsalted butter is beaten with dark brown sugar and spices into a batter, then melted through dark rum with water just off the boil, which gives the mug its body and gloss. Use unsalted, so the sugar and spice set the flavour.

Quick Facts

ABV0%

Legal categoryFood

OriginMade wherever there is a dairy industry

Flavour Strengthlight medium

SeasonAutumn and winter (primarily)

Our keeping timeRefrigerated and wrapped, to the date on the pack. Hot Buttered Rum batter: up to two weeks refrigerated.

Storage

Refrigerated and wrapped, away from strong smells. Soften at room temperature before beating.

Allergens

Contains: milk.

The ingredient

About Butter

Flavour Profile

Primary Flavours

Creamy fatMild dairy

Tasting Notes

Rich, smooth mouthfeel with subtle dairy sweetness. Butter adds body and warmth rather than dominant flavour when used correctly.

Mostly milk fat, by law

Butter is cream churned until its fat separates from the buttermilk. UK law, retained from the EU, sets butter at no less than 80% and under 90% milk fat, with at most 16% water. That fat is what a hot drink borrows: body, gloss and a rich finish that sugar and spirit alone cannot give.

The batter is made ahead

Our Hot Buttered Rum beats 30g of softened unsalted butter with 15g of dark brown sugar until pale, then cinnamon, allspice, clove and vanilla. Multiply it by the number of drinks; we keep it in the fridge for up to two weeks. Each mug takes about 50g of batter, 60ml of dark rum and 150ml of water just off the boil.

Butter in a drink: three ways in

Spiced batter

How it goes in: Beaten with sugar and spice, melted by hot water
Fat in the glass: All of it, emulsified
Keeps: Up to two weeks refrigerated

Melted straight in

How it goes in: A knob stirred into a hot drink
Fat in the glass: All of it, prone to a slick
Keeps: Make and drink

Fat-washed spirit

How it goes in: Infused, frozen, the fat lifted off
Fat in the glass: Very little
Keeps: As the spirit, once strained

Method	How it goes in	Fat in the glass	Keeps
Spiced batter	Beaten with sugar and spice, melted by hot water	All of it, emulsified	Up to two weeks refrigerated
Melted straight in	A knob stirred into a hot drink	All of it, prone to a slick	Make and drink
Fat-washed spirit	Infused, frozen, the fat lifted off	Very little	As the spirit, once strained

Just off the boil keeps it glossy

Butter melted into a hot drink is an emulsion of fat in water. Boiling water breaks it, and the fat floats up as grease. Water just off the boil, a warmed mug and steady stirring keep the fat spread through the drink until it looks glossy. Stir until the surface shines and no yellow beads gather at the edge. Unsalted or salted, butter is dairy, so the mug contains milk as an allergen.

Using it

Using Butter

Usage

Beat 30g of softened unsalted butter with 15g of dark brown sugar and the spices, spoon about 50g of batter into a warmed mug with 60ml of dark rum, and stir in 150ml of water just off the boil until melted through.

Pro Tip

Warm the mug with hot water and empty it before the batter goes in. A cold mug sets the butter at the rim before it melts through.

Top Tips

Soften the butter at room temperature before beating. Cold butter will not take the sugar.
Make batter for several drinks at once; we keep it in the fridge for up to two weeks.
Use water just off the boil. Boiling water separates the fat into a slick on top.
Stir until the drink looks glossy, not merely mixed.

Possible Substitutions

Clarified butter (ghee) – cleaner fat, less dairy flavour

Production Method

Cream churned until the fat clumps and separates from the buttermilk, then washed and worked into a block. Under Regulation (EU) 1308/2013, retained in UK law, butter is at least 80% and under 90% milk fat, with no more than 16% water.

Go further

More to explore

Common Questions

How do you make Hot Buttered Rum?

Beat 30g of softened unsalted butter with 15g of dark brown sugar, cinnamon, allspice, clove and vanilla. Spoon about 50g of the batter into a warmed mug, add 60ml of dark rum and 150ml of water just off the boil, and stir until it melts through.

Salted or unsalted butter for Hot Buttered Rum?

Unsalted, as our recipe says, so the sugar and spice set the flavour and you decide the salt. Salted butters vary in how much they carry. If salted is all you have, it works; taste the batter and leave out any extra pinch.

How long does Hot Buttered Rum batter keep?

Up to two weeks in the fridge, covered, which is our recipe’s limit. Butter takes up other smells easily, so keep the batter in a sealed tub. Let a spoonful soften for a few minutes before it goes in the mug.

Why is there grease on top of my Hot Buttered Rum?

The water was too hot or the drink was not stirred enough. Boiling water separates butter into a slick. Use water just off the boil, stir steadily until the drink turns glossy, and make sure the batter was beaten smooth with the sugar.

What is fat-washing?

Melted butter is stirred into a spirit, left to infuse, then frozen so the set fat can be lifted off and the spirit strained. Fat-soluble flavour stays behind in the spirit. The washed spirit still came into contact with milk, so treat it as containing milk.

Can I use a dairy-free butter?

A plant-based block made for baking beats into a batter and melts in the same way, so the mug carries no dairy. It tastes less of dairy, so the spices carry more of the drink. Check its label for other allergens.

How long does butter keep?

To the date on the pack, refrigerated and wrapped. Butter is mostly fat, so it keeps better than milk or cream, but it picks up fridge smells and goes rancid in warmth and light. Once beaten into batter, our limit is two weeks.

Sources.

Correct as of 17 October 2026.

legislation.gov.uk, “Regulation (EU) No 1308/2013, Annex VII, Appendix II: spreadable fats (as retained in UK law)”.

Make something

Made with Butter

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Hot Buttered Rum

Often Used With

Updated 17 October 2026

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