Rum sour

This rum sour is a wonderfully flavorful twist on the sour cocktail theme, with dark rum, lemon and a touch of sweet. With a lovely depth of flavor, it's refreshing yet feels more complex, despite being so easy to make. Perfect for sipping.

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I have some cocktails that I will only make now and then, or will only have while out as they use ingredients I don't have or take too long. Then there are others I make more regularly as they are both easier and have the kind of flavors I enjoy. Sours are definitely one of my top groups.

What is a sour cocktail?

A sour is a group of cocktails that share a similar core recipe, but with a whole range of variations.

Sours have three core components:

• A spirit/liquor base - whiskey is of course one of the best known, but you can also use gin, brandy and less common bases like in my calvados sour
• A 'sour' component, typically citrus juice - many sours are made with lemon, with lime probably the next most popular. 
• A sweetener, typically simple syrup - this helps to balance the flavors of the drink.
• Many also use some bitters in there for a little extra depth of flavor, and egg white for texture.

Some accounts suggest the basic sour style was created based on sailor rations. Lime or lemons were common on board ships as a way to help prevent scurvy. Given many enjoyed a drink, too, it's no big leap the two merged. Another argument is the citrus watered down the spirit to save the sailors drinking too much too fast.

These days, variations on the sour theme are a core to most bar cocktail menus, and they are great for making at home, too, since they are easy to make and easy to adapt.

For example you can add in a fruit component as in a maracuya sour (passion fruit pisco sour) or tweak the sweetener, as in my pumpkin spice whisky sour. 

What's the difference between a rum sour and a daiquiri?

Technically, a daiquiri is a type of rum sour as it has all the core components of a sour cocktail, and similar proportions to the classic too.

However, when you talk about a rum sour recipe, you generally mean a combination that uses dark rum and lemon juice, rather than the white rum and lime in a daiquiri. Daiquiris generally don't include bitters or use egg white, either.

Ingredients in a rum sour cocktail

For this variation, I've kept things relatively simple but with a couple tweaks that help get the best mix of flavors.

• Dark rum - the main ingredient here is rum, and dark rum is far and away the best choice. You get a lovely depth of flavor with hints of caramel and vanilla that lighter rums don't have. It's worth using one with a good flavor to it, as it will come through, but at the same time don't go overboard with your most expensive bottle. Save that for sipping!
• Lemon juice - the classic choice for a sour and one that works well here. 
• Coconut sugar simple syrup - this is where I have strayed most from the 'typical' simple syrup made with regular sugar, though that works too. I felt it was worth using a sweetener that compliments the rum, and coconut sugar is a great choice. It has some of those more caramel-molasses flavors and a hint of coconut. If you don't have coconut sugar, then I'd suggest using muscovado sugar or at least brown sugar.
• Angostura bitters - a few drops of bitters adds to the depth of flavor, and aromatic bitters work really well. You could also use orange bitters that would also be a good pairing.
• Egg white - while not all sours use egg whites, it's a common choice to add that wonderful smooth mouthfeel to the drink. It takes the drink from flavorful to luscious. If you are nervous about using raw egg white, you can skip it. You can use aquafaba (the chickpea can liquid) as an alternative, though I don't find the texture quite as good.

Tips for making a rum sour

This drink is quick and easy to make as it's as simple as shaking everything together. However there are a couple things that are worth bering in mind. First, I recommend making the syrup ahead of time so that it's ready for when you need it, as well as not being warm. You can make a batch and store in the fridge to use over a few weeks. 

Secondly, use fresh lemon juice. It's easy to squeeze a lemon and the flavor is definitely better with freshly squeezed juice. 

The final tip is to double shake the cocktail, first dry (ie without ice) and then secondly a wet shake (with ice). This helps to build the texture of the foaminess, and cools it down without over-diluting. Strain the cocktail into a glass with ice and enjoy.

If you don't have a cocktail shaker, then it's probably best to skip the egg white. You can try shaking the ingredients in a jar, but I don't find you get quite the same smooth texture in the end drink. (Plus, cocktail shakers are handy for lots of cocktails, so you may find many more uses for it!) 

If you like, you could garnish the drink with a few dots of bitters on the top, or with, for example, a dried citrus slice. However, especially with the foamy top, this works well ungarnished, too.

This rum sour cocktail is easy to make, refreshing yet with a lovely depth of flavors. It's wonderful to sip on, whatever the season, and is definitely one to enjoy soon.

Try these other easy cocktails:

• Mexican carajillo (an easy coffee cocktail)
• Blackberry bourbon smash (a tasty mix of fruit, citrus and a whisky kick)
• Sloe gin fizz (easy to make but tastes more complex thanks to the sloe gin's flavor)
• Rum old fashioned (another rum take on a classic)
• Plus get more cocktail recipes in the archives.

See some of my favorite cooking tools and ingredients in the Caroline's Cooking Amazon store. 

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