Conor McGregor's whiskey is officially one year old ... but the UFC superstar didn't celebrate by getting himself a present -- he's donating a MILLION dollars to a good cause instead!!
The Notorious announced the milestone of his Proper 12 whiskey on Tuesday ... showing off his pipes by singing "Happy Birthday" to the green bottle and holding up a cake.
"What a journey it has been so far!, Conor said on Instagram. "I am so thankful to you all for your support and love of PROPER No. TWELVE!"
McGregor revealed his company's got a master plan to give back .