The “Texas Rattlesnake” cocktail contains no rattlesnake, but it does have a bite. The usual ingredients are Yukon Jack Canadian whisky, cherry brandy, Southern Comfort, and sweet and sour mix.
   
The cocktail date to at least 1998; it is not known who invented it. A “Texas Rattlesnake” cocktail can be found at many restaurants in the Texas Roadhouse chain.
     
   
The Webtender
Texas Rattlesnake
Ingredients:
1 part Yukon Jack
1/2 part Cherry brandy
1 part Southern Comfort
1 splash Sweet and sour
Mixing instructions:
Mix all ingredients and Shake well. Sweet at first, with a BITE at the end…
 
Drinks Mixer
Texas Rattlesnake recipe
1 part Yukon Jack® Canadian whisky
1/2 part cherry brandy
1 part Southern Comfort® peach liqueur
1 splash sweet and sour mix
 
Mix all ingredients and Shake well. Sweet at first, with a BITE at the end.
   
Drink Nation
TEXAS RATTLESNAKE
Ingredients
1 part Brandy, cherry
2 parts Southern Comfort
2 parts Yukon Jack
1 splash Sour Mix
Glass to Use
Shot glass
Mixing Instructions
Shake ingredients in a cocktail shaker with ice. Strain into a shot glass.
 
Orlando (FL) Sentinel
Texas Rattlesnake
1 ounce whiskey
1 ounce Southern Comfort
1/2 ounce cherry brandy
A splash of sour mix
 
Shake ‘em all and pour into any glass you’d prefer. Choose the cocktail glass, though, and a duel might be on the horizon.
 
BEST PLACES TO FIND ONE
Where to get one? The Texas Roadhouse in Bethlehem. Try to find another place in our area where the floor’s covered in peanut shells, the steak is as good, and the friendly-looking waitresses do a little dance by the bar.
 
Google Groups: alt.alcohol
Newsgroups: alt.alcohol
From: .(JavaScript must be enabled to view this email address) (Mmmk78)
Date: 1998/06/17
Subject: Re: RATTLESNAKE
 
There are a few different types of RATTLESNAKES you can make:
 
Rattlesnake Shot:
Yukon Jack
Cherry Brandy
Sweet and Sour
 
Rattlesnake:
1 Bailey’s Irish Creme
1 Kahlua
1 Creme de Cacao
   
Rattlesnake Cocktail:
1 1/2 oz. Blended Whiskey
1 tsp. Lemon Juice
1/4 tsp. Anise
1/2 tsp. Powdered Sugar
1 Egg White
 
Texas Rattlesnake:
1 part Yukon Jack
1/2 part Cherry Brandy
1 part Southern Comfort
splash Sweet and Sour
 
I’m guessing that you were probably referring to a Texas Rattlesnake since you mentioned SoCo, but here are the “recipes” for all four kinds of Rattlesnake.
Enjoy!