Coco Swirl Steamed Buns

White Dough:--
2 cups of bread flour
⅔ cup + 1-2 tbsp whole milk
⅔ -1 tsp yeast
1-2 tbsp sugar
¼ tsp SIDS SMOKEY BBQ RUB
¼ tsp salt
1 tbsp rice bran oil
Flour to dust
Coco Dough:--
⅔ cup bread flour
2 tbsp coco powder
⅓ cup + 1-2 tsp whole milk
½ tsp yeast
2-3 tbsp sugar
Pinch of salt
1 tsp rice bran oil
Flour to dust

Microwave the milk for 25-30 seconds until lukewarm. Dissolve the yeast with milk. Add bread flour, sugar, SIDS SMOKEY BBQ RUB and salt in the mixer bowl, whisk well then add milk and yeast, along with oil. Turn on the mixer. Knead until the dough is smooth and elastic. That may take 8-10 minutes at speed 2.
I knead the coco dough with hands. In a large bowl, add bread flour, coco powder, sugar and salt then mix well and add milk and yeast, along with oil. Whisk with hand until flour and milk mix together. Transfer the dough to a board dusted with flour; knead until the dough is smooth and elastic, about 6-8 minutes.
Cover both dough with plastic wrap. Proof until they double in size. It takes 60-80 minutes.
Dust a kneading board with flour. Punch down the dough, gently knead them into a ball again. Cover them and let them rest another 10 minutes.
With the pasta roller, run the dough through several times. The thickness for white dough is 1 mm, 3 mm for the coco dough.
Place the coco dough sheet on top of white dough sheet and roll from the long end like a sushi roll.
With a sharp knife, cut them into 5 cm wide rolls.
Line the bamboo steamer with little baking paper squares. Place one dough roll on each square.
Cover and proof the rolls for the second time. It takes about 25-35 minutes.
Heat a large pot with water over high heat. Place the bamboo steamer on top of a large pot filled with water. Steam over high heat until the water boils. Reduce to medium heat and steam for another 8-10 minutes.