There are few forces in the universe quite as compelling as the scent of freshly baked waffles.

When Phyu Hnin Aye got her first sniff while traveling through Germany and France, it changed her life: She became obsessed with making the sweet treats herself. But at her cart Puffle Waffle at Happy Valley Station, the troubled food-cart pod 60 blocks east of Clackamas Town Center on Sunnyside Road, she's making an different waffle entirely.

"Portland is a food city," Aye says. "People here are very eager and willing to always try new things."

Aye's bubble waffles look, as their name suggests, like bubble wrap made of sweet dough—but each of those bubbles is a fluffy egg puff. Though still very rare in the United States, bubble waffles are a ridiculously popular street food in Hong Kong, where they're usually served plain. Aye serves her plain or chocolate waffles stuffed and stacked with Nutella or ice cream flavors from chocolate to matcha, plus a vast array of wild toppings: cookies and cream Pocky, fresh strawberries or blueberries, mochi, M&Ms and a mess of sauces. She makes her waffle dough just a little less sweet than you'd find in Hong Kong, for a beautifully balanced confection. Wrapped up in those bubbles, it looks a like a whole candy store just arrived in the mail.