If i told you, you have to drink 12L of milk with a spoon. How would you do it?

You forgot to add a timeframe ;)
I would let you choose:

The long way:
Provided that the milk is in good condition throughout, I would get the biggest spoon I can, put some movies on and get a spoon of milk every now and then for.. I think it would take me 3 to 5 days. If I get bored, I'll put some teas of different flavors in it and/or some coffee.

The short way:
Another solution would be... make cheese from the milk and eat it with a spoon (with maybe some spices) :P. I wonder how much cheese can come out of 12L milk.. since it would be in condensed form, I could eat that in a day or two! :)

The emotional way:
Turn it into ice cream and eat it together, because I am 99.99% certain that you wouldn't be able to resist eating your emotions with me. I bet that would take a day or two as well (or less, if you are very hungry).

Sometimes, I wish I really had the free time to do a weird challenge like this xD

Hold the spoon in my hand while chugging the milk

One spoon at a time

Slurp slurp 800 times

😠
I love my digestive system more than that spoon and your post.