It's not quite "How I Met Your Father" -- not yet, anyway -- but Kristin Cavallari's explaining how she bagged her much younger boo, Mark Estes, and like most things these days, it started with her scrolling.
Kristin spilled the tea on her "Let's Be Honest" podcast ... she says she was casually watching TikTok vids in September, when she stumbled upon Mark's group Montana Boyz, and he caught her eye as the hottest one.
She then moved on with her life -- until fate swooped in 3 weeks later, bringing them together.