Stir in dry yeast in lukewarm water to break down lumps. Set aside.
Mix flour, sugar, baking powder and salt for dough in a separate bowl.
Add the yeast liquid into dry ingredients and knead with hands until a ball is formed, about 5 minutes. If the dough is too wet (i.e., sticks to your hands after you bring together the flour and knead for a couple of minutes), knead in 1~2 tablespoons of flour, 1 tablespoon at a time.
Add oil and knead until a smooth ball is formed, about 5 minutes. Cover with plastic and let it sit in a warm space until the dough doubles in size, about an hour. You can speed up this step by placing the bowl on top of a pot with hot water. Make sure the bowl is not touching hot water.
In the meantime, mix all ingredients for the spicy turkey filling. Set aside.
Pour water to about 1/2 high in the pot and bring up to a boil.
Also prepare 6-8 paper cupcake liners or about the same size parchment paper pieces.
Once the dough doubles in size, knead it down to remove gas. Put a few drops of oil on your palm so that the dough won't stick to your hands. Divide the dough into 6 pieces (almost a meal size) or 8 pieces for a snack size.
Shape the dough into a ball, flatten it then press the edges to make it thinner than the middle part. Place about 2 tablespoons of the filling in the middle. Carefully bring the edges together and seal with fingers. Place the sealed part down touching the paper liner. Repeat with the rest of the dough balls.
Bring the water in the pot to a boil again. Place the steamer on top of the pot. Steam for 15 minutes with the lid on while the water is consistently boiling over high heat. After 15 minutes, buns should be almost double the size with a smooth surface. Remove from heat and let them sit for 5 minutes with no lid. Be careful touching the steamer, it's very hot.