"Oh, you motherf--ker. It is bad," the actress said at one point. "Oh my god!"
While appearing on the latest episode of the popular YouTube series, released Thursday, the actress, 29, proved she's a spicy food champion but -- like many stars before her -- it definitely wasn't an easy ride.
Despite a little burning, Stewart made it through multiple hot sauce-dunked vegan cauliflower wings as she answered host Sean Evans' various questions like her views on living in Los Angeles. However, the "Twilight" alum knew the ultimate hurdle was upon her: Da'Bomb, the same hot sauce she noted brought Charlize Theron to tears.
"It's this one though," she said before facing the spicy wing. "This is what made Charlize like...I'm scared of this one."
After taking a bite, Stewart concluded that the heat wasn't too hot and pointed out how "everything is not as bad" as she often anticipates it to be. A few seconds later, the star's opinion on the sauce flipped as the spiciness hit her all at once.
Interrupting Evans' question, Stewart smiled and said, "Oh, you motherf--ker. It is bad."
KStew was seemingly determined to answer the questions, but couldn't bypass the heat and kept cursing as she tried to deal with the pain.
"What the f--king?!" she said between replies. "F--k you hard, in the face!"
With two more sauces to go, Stewart tried to remain positive. "I think the worst is behind us, right?" she said and then noted, "It's the back of your mouth that sucks. It's like the esophagus."
After making it through nine sauces, the "Into the Wild" actress only had one last dab to go. To make it more fun, she brought out her "Charlie's Angels" co-stars Naomi Scott and Ella Balinska, the latter of whom had much more trouble.
And Stewart, who was in tears at this point, took the final dab like a champ. "Together, we are stronger and hotter," she said. "So I feel like this is going to be good."
Watch it all go down in the full interview, above.
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