The Dirty Wastelander
While there are plenty of consumables in the Fallout universe, this is a first when it comes to mixed drinks (unless you call Nuka Cola Quantum a mixed drink. But instead of alcohol it's the goo inside glow sticks).
In any case, whether you're looking to relax and unwind in your settlement, or just want to get a boost on your strength and charisma - while sacrificing some intelligence and brain cells - this is the drink for you.
What you'll need:
Mutfruit (Blackberries, for our purposes)
Whiskey, of your choice
Step 1: Empty blackberries into medium sized bowl, and use a soup spoon to crush said berries roughly.
Step 2: To keep it truly dirty (while also having washed your hands), grab those berries and squeeze 'em over a sieve or strainer to get the most juice without pulp.
Step 3: Grab your rocks glass (and add your ice, if you so choose).
Step 4: Pour in 1 and 1/2 oz of whiskey.
Step 5: Fill the rest of the way with cola.
Step 6: Add 1 tbsp of your mutfruit juice, gently stirring.
And there you have it! A cocktail known the wasteland over, enjoyed by raiders, gunners and minutemen alike. Drink responsibly, ya crazies.