Recipe courtesy of TASTE Cocktails: The first printed mention of an Old Fashioned was in 1806, however as with many drinks the official creator is quite a mystery. According to some the Old Fashioned was created by James E. Pepper, a bartender at a social club in Louisville, Kentucky. Throughout the 1800's and into the 1900's there were many mentions of the Old Fashioned in books including in the 1895 "Modern American Drinks" written by G. Kappeler in which the classic recipe below is found.
50ml Buffalo Trace Bourbon, 3-4 dashes Angostura Bitters, 5-10ml Sugar or sugar syrup, large slice of orange peel
Add sugar to a rocks glass and then soak it with the bitters. Measure your bourbon, and pour it in just a splash, then add 1-2 ice cubes and stir to dissolve the sugar. Add another splash of bourbon, another couple of cubes, stir again and repeat that process until all the bourbon is used and the glass is full of ice. The whole thing should take a few mnutes at least, so that the drink is diluted and cooled.