Recipe

Hong Kong Bubble Egg Waffles

Street style egg waffles with crisp edges, a tender custard-like center, and golden bubbles made for ice cream, fruit, and syrup.

By Matt Campbell

•

4.8

A freshly cooked Hong Kong bubble egg waffle folded into a cone shape on parchment paper, golden brown with crisp bubbles and a soft custardy interior visible, natural window light

Jump to Recipe

Bubble egg waffles, also called gai daan jai, are the kind of snack that makes you stop mid-bite to do a quick reality check. How is it this crisp on the outside, but still soft and custardy inside? The secret is not just the cute bubble iron. It is the batter, the heat, and a couple small moves that feel fussy the first time and then become second nature.

This is Cantonese street style at home: accessible ingredients, clear steps, and enough guidance so you can get that signature crisp edge vs tender middle texture without stress. We will talk about starch options (including tapioca for that gentle chew), iron temperature, sweet and plain variations, and the best way to serve these while they are still doing that warm, toasty vanilla-egg thing.

A stainless steel mixing bowl with pale yellow bubble egg waffle batter being whisked until smooth on a home kitchen counter

Why It Works

Two leaveners, two jobs: baking powder gives reliable lift. A small amount of baking soda mainly helps browning and a lighter texture once it hits the hot iron.
Rest time matters: a short batter rest hydrates the flour and thickens the batter slightly, which helps pocket fill and keeps the center tender instead of bready.
Heat control equals texture: a well-preheated iron sets the outer shell fast for crisp edges, while the thicker batter in the bubbles stays soft.
Flip only if designed for it: flip-style irons benefit from a quick early flip to push batter into the pockets. Non-flip electrics should stay closed and follow manufacturer guidance.
Steam is the enemy of crisp: cooling on a rack keeps the bubbles snappy instead of soggy.

Pairs Well With

Storage Tips

Bubble egg waffles are at their absolute best in the first 20 minutes, when the shell is still crisp. That said, leftovers are totally salvageable. The timelines below are about best quality, not strict safety cutoffs.

To store

Room temp (same day): Let waffles cool fully on a rack, then keep loosely covered. Tight containers trap steam and soften the crust.
Fridge (best within 2 days): Store in an airtight container. Expect the exterior to soften.
Freezer (best within 1 month): Freeze flat on a sheet pan, then transfer to a freezer bag. Add parchment between waffles if stacking.

To re-crisp

Toaster oven or oven: 350°F for 5 to 8 minutes, directly on the rack.
Air fryer: 350°F for 3 to 5 minutes.
Avoid the microwave unless you want soft pancake vibes. If you must, microwave briefly then finish in a toaster oven.

A bubble egg waffle reheating on the rack of a toaster oven with the bubbles turning crisp and lightly browned

Common Questions

Do I need a bubble waffle iron?

For the classic bubble shape, yes. A bubble waffle iron has the deep spherical pockets that create the pull-apart “bubble” texture. A standard waffle maker will still taste good, but it will be a different waffle.

Why is my egg waffle not crispy?

Usually one of three things: the iron was not hot enough, the waffle was undercooked, or it cooled on a plate (steam trapped underneath softens the shell). Preheat longer than you think, cook until deep golden, and cool on a rack.

Why is the inside bready instead of custardy?

Overmixing can build gluten, and too much flour makes it breadlike. Whisk just until smooth, measure flour correctly (spoon and level), and let the batter rest so it hydrates and cooks more evenly.

Can I make the batter ahead?

Yes, but it is best within 12 hours for top texture. Cover and refrigerate, then whisk briefly before using. The batter may thicken a bit, so add 1 to 2 tablespoons milk if needed to get back to a thick pour.

What oil should I use to grease the iron?

Use a neutral, high-heat oil like canola, avocado, or grapeseed. Butter tends to burn on the hot plates.

Is custard powder required?

No. Many home recipes use it for a more street-style aroma and color. If you do not have it, you can skip it and add 1 extra tablespoon cornstarch plus a little extra vanilla for a similar tender bite. If you are shopping, look for vanilla custard powder (often the Bird’s style), which is typically sweetened.

What about tapioca starch?

If you want that more traditional Hong Kong “Q” bounce in the center, swap the cornstarch for tapioca starch (or do half and half). Cornstarch leans crisp and tender, tapioca adds a gentle chew.

Matt Campbell

I have always had a huge passion for the culinary arts, people, working as a team, and so on. I wanted to pursue my love for cooking initially at Virginia Commonwealth University with a culinary arts degree; however, I instead decided to apply myself and acquire more practical skills. My end goal is to eventually open my own restaurant or similar establishment.

Kitchen Essentials

Bubble waffle iron (flip-style pan or electric countertop model)
Mixing bowl
Whisk
Fine-mesh sieve (optional, for extra-smooth batter)
Measuring cups and spoons
Pastry brush or paper towel for oiling plates
Wire rack for cooling (important for crispness)

The first time I made these, I treated the iron like a normal waffle maker and expected it to magically do the street-food thing on its own. It did not. I got pale bubbles and a soft shell that tasted fine but felt like it missed the point. The next round I cranked the preheat, rested the batter, flipped early (on the flip-style pan), and cooled them on a rack. Suddenly: crisp edges, that warm eggy vanilla scent, and the weirdly satisfying moment of pulling off a bubble like it is edible packing foam, but actually delicious.