Kourtney Candy-Shames Kim Over Candyland-Themed Birthday Party in 'KUWTK' Preview -- This Is Not a Joke!

If fans thought the fallout from the Jordyn-Tristan cheating scandal would be the biggest crisis to hit "Keeping Up with the Kardashians" upcoming new season, they are set to be in for a huge candy-shaped surprise.

In what started out as an adorable exchange between sisters over a candy display discovered (shockingly) at Kourtney's house, things quickly turned deadly serious and surprisingly ugly between Kourtney and Kim over the party planning for North and Penelope's upcoming joint birthday celebration.

At first it was just some light-hearted teasing from Kim and Khloe, shocked to find candy even in Kourtney's house. She quickly explained, thought, that Kris Jenner is fully to blame for that. And as her sisters started sampling the candy goodness, Kourtney took court from her couch and proceeded to shame them mercilessly.

"That's my only hidden stash of candy and I wouldn't have had it here. So you guys fill yourselves up," she said with a wicked smile. "The biggest number one cause of aging. Don't you just feel it when you eat that that it like sucks the life and youthfulness out of your skin?"

"It makes me feel like a kid inside," Kim said, but Kourtney was having none of it going on about all the "disgusting chemicals" in candy.

She then pivoted to wanting to talk about planning the kids' birthday parties, but it wasn't as much a change of subject as you might have thought as Kourtney immediately started laying into Kim's plan to have candy at the party ... at the Candyland-themed party, as Kim reminded her.

"There's candies that are not disgusting and filled with chemicals," Kourtney told her younger sister, who challenged her to show her some, then.

"Do you want me to make you a collage or posterboard?" Kourtney said with a smart-alec smile.

Kim responded in kind, as tensions escalated and Khloe very pointedly focused intently on her phone. You could practically hear her thinking, "I'm not here. I'm not here."

"Make me a f--king pinata," Kim told Kourtney. "All that shit, and I'll hit it with your face."

Finally, the girls reached the point where sarcasm and jokes weren't going to cut it and just started yelling at each other over the presence of candy at this Candyland-themed party. "But everyone's going to come to this party and everything's going to be disgusting chemicals," Kourtney argued." You need to have some healthy options."

Kim then suggested Kourtney just change the whole theme of the party, then, if she was determined to ruin it. But Kourtney had an even more drastic suggestion.

Check out the explosive confrontation -- and wonder what Khloe was looking at so intently on her phone -- in the video above as the Kadashians return for a new season of "Keeping Up with the Kardashians" in the fall!

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