How to make a fat wash brown butter infusion

How to make a fat wash brown butter rum infusion

A short guide to fat washing and how to make a brown butter washed rum

Fat washing might sound like a complicated lab procedure but it’s surprisingly easy to do. If you’ve always been curious about what it is, and how to do it, read our guide below.

What is fat washing?

At its core, fat washing is infusing an alcohol with a certain fat in liquid form. Common fats used are butter, oil (olive, sesame, peanut) and the most famous of all, rendered bacon fat. It’s a great way to infuse alcohol with flavour from the fats without the greasiness. The infused alcohol generally also has a more well rounded texture - depending on the fat you use, you might find your infused spirit with a more unctuous or silky velvet feel.

When did fat washed cocktails become a thing?

Fat washed cocktails really rose to fame in about 2007/2008 in New York at the speakeasy bar PDT. Its creator Don Lee infused Benton bourbon with bacon fat to create the Benton’s Old Fashioned that became wildly popular. It wasn’t an entirely original idea - Lee picked up the technique from fellow bartender Eben Freeman who was working at WD-50 bar at the time.

How to fat wash?

Firstly, if the fat you are looking to use is in solid form (butter, lard, bacon fat), you’ll need to reduce it to liquid form. With bacon fat, this means you will have to fry the bacon in order to tease out the liquid oils from the fat. (i.e. it’s not a case of cutting off the fat bits of the bacon and dropping it into the liquor!) It’s important to use as good quality an ingredient you can afford as it’ll make all the difference.

You then add the liquid fat to the liquor of your choice at room temperature. Put the whole thing in the fridge. The fat will then solidify and rise to the top. Depending on how long you let the infusion sit, you then remove from the fridge and strain out the solidified fat. Generally, you’ll be able to use a muslin cloth that you put the liquid in, and the muslin cloth will capture the solid fats. If you’re pedantic, you could go through a second straining by using a coffee filter.

For our experiment, we’ve decided to make fat wash rum with some browned butter.

How to make a brown butter fat wash rum

What you need

  • 60g butter

  • 150ml rum

Instructions

  • Heat a pan

  • Lower the fire to a low heat and drop the butter in

  • Fry the butter until it turns brown

  • Turn the heat off. Pour rum into the pan and gently mix

  • Pour the whole rum-butter mix into a container

What the brown butter rum infusion looks like out of the pan at room temperature

What the brown butter rum infusion looks like out of the pan at room temperature

  • Leave the closed container to chill in the fridge for a day

  • Remove the container and scoop off the fat which should have re-solidified at the top of the liquid.

  • Strain the liquid through a muslin or cheese cloth to capture any remaining fats

  • Store the rum in the fridge

PS Don’t throw away the re-solidified butter! You can use it in cooking too!

The re-solidified butter is great for making roast potatoes and in cooking steak and gravy!

The re-solidified butter is great for making roast potatoes and in cooking steak and gravy!