As of 2016, Epicurious.com offers a recipe for a Moscow Mule with a user rating of 4 out of 4. Required ingredients for the recipe are half of a lime, 2 ounces of vodka and 4 to 6 ounces of ginger beer, preferably from the Cock'n Bull or D&G Old Jamaica brands.
AllRecipes.com has a Moscow Mule recipe rated 5 out of 5 stars that requires similar ingredients such as 1 1/2 ounce vodka, 1/2 ounce lime juice, ice cubes and a 1/2 cup ginger beer along with a lime wedge for garnishing.
To make the recipe from Epicurious.com, squeeze the half a lime into a Collins glass or copper mug, then drop in the remaining half of the lime, including the rind. Fill the glass with two to three ice cubes, and pour the 2 ounces of vodka in the glass, followed by the ginger beer. Serve the drink with a stirring rod.
For the AllRecipes.com Moscow Mule recipe, pour the 1 1/2 ounces of vodka into a glass, and add the 1/2 ounces of lime juice; then fill the glass with ice cubes and top it with ginger beer. Stir the cocktail to combine all ingredients, and finish off the drink by dropping the lime wedge into the glass for garnish.