A rim of salt or sugar on the edge of a glass is a great way to add another layer to a cocktail give it some visual contrast. The most familiar example of this is of course the salt rim on a Margarita, which not everyone is a fan of (I, personally, am). Sugar is also common, most notably on a Sidecar. Though just about anything that is granulated or powdered in your spice cabinet is fair game, more on the below.
There a few different approaches to rimming a glass. But all of them involves wetting edge to create as an adhesive for the granules to stick onto, and then dipping the glass into a some salt, sugar, or whatever you want.
Rim Mixes with Spices
When rimming a glass with something other than sugar or salt - black pepper, cayenne powder, pink peppercorn, celery salt, garam masala, cinnamon, etc. - it’s best to blend it with some salt and sugar. Most of these spices are too intense on their own. This helps to balance and accentuate their flavors. Here’s a good rule of thumb ratio to use as a starting point.
4 parts sugar
1 part salt - only use with savory spices.
1 part spice of choice
Rimming a Glass
Step 1 - Wet the Edge of the Glass
The conventional method is to use a citrus wedge, but there are plenty of way to get the edge of a glass wet. You could even use a wet paper towel. Here are three common methods. Another approach you could use at home that is not pictured is a wet paper towel.
Rub the rim of the glass with the flesh side of citrus wedge, or any piece of cut citrus. Ideally you should use the same type of citrus that is used in the drink.
Gently dip the glass' edge into a container of simple syrup. Not surprisingly, simple syrup forms the strongest glue. It's best with sugar or other sweet flavors, it makes them almost like a candied rim. Though simple is also potentially messiest, so apply it gently. You don't want it dripping down the sides of the glass.
Freeze the Glass
(My Preferred Technique)
Put the glass in the freezer for 10 minutes or more - which is generally a good idea anyway - and take it out about 30 seconds before serving. As the glass warms up, the condensation that forms on the edge will serve as the adhesive. Not only does this method skip a step, but it also creates an even amount of moisture, so you're able to make cleaner and more consistent rims. See the "thick rim" below.
For this type of rim it’s best to use a plate because it needs to fit the entire circumference of the glass. Otherwise you’d need a big bowl filled up almost all the way with the salt/sugar/etc., which would be a waste if you're only making a couple drinks.
Dip the glass head first into the salt/sugar and twist it a few times so the entire rim is coated.
With this approach it’ll almost always be a full rim, though a partial one is possible. Also, because both sides of the glass are coated, some of the rim will fall into the drink, if that makes a difference to you.
Step 2: Apply the Rim
Regardless of how you apply your “glue”, one it’s on there you’ll want to quickly add the rim before the glass dried. You can take a few different approaches to rimming. The two main questions are a thick vs. fine rim, and a full vs. partial rim.
A thick rim covers a broader swath on the outside of the glass, generally about a half inch wide, while a fine rim is a crust just around the lip of the glass, sort of like a crust. A partial rim means that only part of the circumference of the glass’ edge is covered, usually about half. This gives the drinker the option of licking off some of the rim when they take a sip, or not. Given that, naturally a full rim means the entire edge is coated, and the drinker has no choice but to dive in.
Repeatedly dab the edge of your glass into the bowl in small increments - don’t roll or drag it across - until you’ve coated as much of the rim as you’d like. Ideally, it should just be on the outside of the glass and none should fall into the drink (but it’s no tragedy if it does).
Fill a small bowl or plate with your rim. Make sure it’s wide enough to fit the glass you’re using.
This method is a good candidate for a partial/half rim, because you have more control of how much gets on there. But it’s up to you.
Thick Rim (My Preference)
I personally like thick rims because they provide more flavor and look pretty.
Storing Rim Mixes
Rims should be kept in a dry place, like a cupboard. I store them in tupperware containers. Note, while it may be convenient to rim glasses right in the storing vessel, over time the batch will become sticky and take on the consistency of wet sand. This is because every time you rim a glass you’ll be adding a little bit of moisture, whether you’re using citrus juice, simple syrup or condensation.
So each time you use the rim, it’s best to pour a little onto a plate or small bowl and then return it to the batch when you’re done.