A chili taco supreme is when you stay up all night eating taco bell and drinking mountain dew. The next morning when your girlfriend comes over, you have diarrhea on her snatch and sprinkle cheese, lettuce, and sour cream before eating her out.
"Omg babe, that chili taco supreme you gave me was the hottest thing you've ever done. I still can't walk right"
A chili taco is when you eat spicy Mexican food and drink mountain dew all night. The next morning, you invite your girlfriend over and have diarrhea in her snatch. You use the spicy Mexican diarrhea as lube.
"Hey babe, don't forget to pick up taco bell on the way home from work. Let's cancel dinner with your parents so you can give me a chili taco"