Spicy Chinese Chicken: Combine all ingredients except for sugar and corn starch in shallow pan or large resealable plastic bag. Refrigerate and marinate overnight or for at least 6 hours.
Preheat oven to 350ºF. Line an oven proof pot with aluminum foil, add the chicken including the marinade. Cover and cook for 30 minutes. Remove the foil and continue cooking for 10 minutes. Remove the chicken and set aside to cool. Strain the pan juices to remove the garlic cloves and set aside to cool. Once cool, shred the chicken and roughly chop.
Combine 1 cup of the reserved pan juices, sugar and corn starch mixed with 1 tablespoon water in a small saucepan. Bring to a boil for 1 minute. Remove from heat and add to the chicken, stirring well to coat all the chicken. Set aside. Can be prepared ahead and refrigerated for up to 48 hours.
Steamed Buns: Combine 3 tablespoons water and yeast in a small bowl; let rest for 5 minutes. Combine 2 cups water, sugar, oil and salt in large mixer bowl with paddle attachment. Add yeast mixture and 2 cups flour; beat until well mixed. Add 1 cup additional flour and beat for 2 minutes. Gradually add enough flour to make a soft dough. Change to dough hook and knead for 6 to 8 minutes; adding only enough flour so that the dough forms a ball. Coat large bowl with sesame oil; coat dough ball with oil. Cover and let rise in warm draft-free area for 30 to 45 minutes or until dough doubles in size.
Punch dough out onto a lightly oiled cutting board. Divide into 24 pieces. Roll each piece of dough into a ball and press or roll into a 6-inch circle. Place a heaping #30 scoop of filling onto each piece of dough. Pinch dough to seal at top.
Set each ball on an oiled square of parchment paper. Place buns in bamboo steamer and steam for 6 to 8 minutes until dough is cooked through. Do not crowd buns. Remove from steamer. Repeat with remaining buns. Garnish with green onions and black sesame seeds or serve with a spicy dipping sauce.
Recipe Note: To make 36 buns, roll or pat each piece of dough into a 4-inch circle. Top with a heaping tablespoon of chicken filling. Steam for 5 to 7 minutes.