Hong Kong Style Pineapple Bun with Butter

Put 220g bread flour, 45g sugar, 3g salt, 40g sourdough starter, 2.5g instant yeast, 125ml milk, and 25g egg wash into the mixer bowl. Knead on speed 4 for 10-15 minutes until it forms a dough with resilience, pulling into an uneven membrane with jagged edges (80% gluten development), with a dough temperature around 22.5°C.

Add 20g softened butter, knead on low speed 2 for about 3 minutes until the butter is fully incorporated into the dough, then switch to speed 4 for another 3-5 minutes until the dough can pull into a smooth-edged membrane with very few jagged teeth, and the final dough temperature is 25.3°C.

Fold the dough with both hands to smooth the surface, place it in a fermentation box or baking pan (cover with a lid to reduce humidity absorption if needed), and ferment in a proofing box at 26-28°C with 75% humidity for about 1 hour until doubled in size, showing a slight spring-back and leaving an indentation when pressed with a flour-dusted finger.

Invert the fermented dough directly onto a silicone mat without degassing, keeping its shape as much as possible, and divide directly into 8 equal portions.

Round each divided portion of dough, folding any small pieces inside, and continue rolling into smooth little balls.

Cover all rounded dough balls and let them relax for 30 minutes (if room temperature is below 23°C, place in a 26°C environment). The relaxed dough will be larger and show slight spring-back when pressed with a flour-dusted finger.

Flatten the relaxed dough, flip it, fold it, pat it, fold again and pat, then roll it round, and finally pinch the bottom closed using your tiger's mouth grip. Place in a baking pan with enough space between each dough ball.

Place the shaped dough into a proofer (30-35°C, about 80% humidity) for the second proof. If you only have one proofer, place the second pan in the oven with a spray of water for room-temperature proofing until doubled in size with slight spring-back and indentations.

Mix 42g softened butter and 45g sugar in a bowl until smooth and creamy. Add 1 room-temperature egg yolk and mix well. Sift in 84g cake flour, 0.5g baking soda, and 7g milk powder, then add 10ml heavy cream. Wear gloves and mix gently into a dough without over-kneading to avoid gluten formation. Divide into 8 equal portions and cover with plastic wrap to prevent drying.

Brush the proofed dough with 25g egg wash. Place the crust dough in a plastic bag, flatten and roll out with a rolling pin (sift a little cake flour if sticky). Peel off the bag and drape the crust evenly over the dough, then brush the top with egg yolk mixed with a little water.

Preheat the oven with top heat at 210°C and bottom heat at 180°C for 15 minutes. Place the assembled buns on the second-to-bottom rack and bake at top 210°C / bottom 180°C for 13 minutes. Tap the pan upon removal and transfer buns to a cooling rack.

Slice the baked pineapple buns (either horizontally like a burger or diagonally without cutting through) and bake in the middle rack of the oven at 230°C top and bottom heat for 3 minutes to make the surface slightly crispy and the inside soft. Meanwhile, heat 1 tbsp cooking oil in a pan over medium heat, crack in 1 egg, season with a pinch of salt and black pepper to make a sunny-side-up egg. Assemble the innovative version by layering butter, tomato slice, and fried egg inside the warm bun, or add cold salted butter for the classic version.