Pastries · FFET10265
Bo lo bao (pineapple bun)
The pineapple bun is a Hong Kong sweet bun with a crisp sugar crust that cracks into a pineapple-skin pattern, with no pineapple inside.
A round white porcelain plate holds milk and butter buns with golden, crisp sugar crusts made with beaten egg and egg yolk, their cracked surfaces resembling pineapple skin, with wooden chopsticks resting beside the plate.
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The pineapple bun is a Hong Kong sweet bun whose dough is covered with a crust of sugar, egg, flour and fat that cracks in the oven into a pattern like pineapple skin, which gives it its name; there is no pineapple inside. It is found in Hong Kong bakeries, tea restaurants and bing sutt cafes, where it is often split and filled with a slice of butter as a bo lo yau. It may have appeared around the 1940s, but its origin is unclear, accounts vary, and no dated text was found.
What
The pineapple bun is a Hong Kong sweet bun covered with a thin sugar crust that cracks in the oven into a pattern like the skin of a pineapple; the name comes from that pattern and there is no pineapple inside. It is often served warm, split and filled with a slice of butter, called a bo lo yau.1,2
When
The bun may have appeared around the 1940s, but its origin is unclear: theories involving Russian bread, Japanese pastry-topped bread and the Mexican concha remain unconfirmed, and no dated text was found to establish an exact year or inventor. A July 30, 2026 report notes that Hong Kong's bing sutt cafes rose in the 1950s and bakery counters appeared in the 1960s.1,2,3
How
A soft bread dough enriched with milk and egg (one of the recipes adds a tangzhong starter) is covered with a disc of topping dough made from butter, sugar, egg and flour, brushed with egg yolk and baked until the topping cracks. For the fat in the topping, bakers use lard or butter. The two recipes bake differently: one at about 175 degrees Celsius for 12 to 13 minutes, the other at 210 for 5 minutes and then 180 for 15.1,4,5
Why
One account in a 2026 Hong Kong report traces the method to a baker putting the topping of Chinese walnut crisps on a small bun during the lean postwar years of bing sutt cafes, with baking soda added later to make the crust lighter.3
Impact and influence
The bun can be split and filled with butter to make a bo lo yau; a 2026 report also mentions a giant version made later.1,3
No tale about this food has been found.
Grandma Li
This is a simplified home version, not the traditional restaurant method.
This is how I make pineapple buns at home. The gram amounts for the dough and the topping follow a recipe blog by a named author, adapted from a Hong Kong bakery owner's lard recipe and made with butter; the tangzhong ratio is my own, since that recipe gives just its weight. A second recipe, by another named author, measures in cups and bakes differently, and I mention its baking only in the tips. The milk powder and milk in the topping are my own amounts.
Ingredients
- Bread flour, for the dough 350 g
- Sugar, for the dough 70 g
- Salt 4 g
- Beaten egg, for the dough 56 g
- Milk powder, for the dough 10 g
- Yeast 6 g
- Tangzhong (20 g bread flour cooked with 100 ml water into a paste, cooled) 120 g
- Milk, for the dough 125 ml
- Butter, for the dough 30 g
- Cake flour, for the topping 125 g
- Sugar, for the topping 55 g
- Butter, for the topping 40 g
- Milk powder, for the topping 10 g
- Milk, for the topping, to bring it together about 10 ml
- Egg yolks (one in the topping, one to brush on top) 2
Steps
- Begin with the tangzhong: stir 20 g bread flour into 100 ml water, cook over low heat stirring until it becomes a paste, and let it cool.
- Put the dough ingredients, except the butter, in a bowl and knead into a dough, then add the 30 g of butter and knead until the dough is smooth and elastic. Cover and let it prove for about 40 minutes.
- Make the topping: soften the 40 g of butter, stir in the 55 g of sugar, mix in one egg yolk, the milk powder and about 10 ml of milk, sift in the cake flour and bring it into a soft dough. Chill it.
- Divide the dough into 12 pieces of about 62 g each, roll them round, cover and rest for about 15 minutes. Divide the topping into 12 pieces too.
- Press each piece of topping into a disc slightly larger than the bun, lay it over a dough ball, brush with the other egg yolk, set the buns on a baking tray and prove them for about 35 minutes more.
- Preheat the oven to 210 degrees Celsius, bake the buns for 5 minutes, then lower it to 180 and bake for 15 minutes more, until the topping has cracked and turned golden.
- Take them out, let them cool slightly and eat them warm. For a bo lo yau, split a bun and put in a slice of butter.
Tips
- The two recipes bake differently: one at about 175 degrees Celsius for 12 to 13 minutes, the other at 210 for 5 minutes and then 180 for 15. I follow the second and also watch for the topping to crack and turn golden; your oven may differ.
- If the topping is too soft to shape, I chill it again for ten minutes before pressing it out; this is my own way.
Allergens: wheat, egg, milk