Cornmeal Bao With Turkey and Black Pepper Sauce

Stir sugar and yeast into 2/3 cup warm (100°) water in a small bowl. Let sit until foamy, about 5 minutes. Whisk flour, corn muffin mix, salt, and baking powder in a large bowl to combine. Stir sugar mixture into dry ingredients, then stir in 2 Tbsp. oil. Mix just until a shaggy dough forms.

Turn dough out onto a work surface. Gently knead just until smooth (be careful not to overwork). Transfer to a lightly oiled bowl and cover tightly with plastic wrap. Let rise in a warm spot until dough is puffed and yields easily when poked, about 1 1/2 hours.

Divide dough into 16 balls and gently roll between your palms until smooth. Roll out each ball to a 6x3" oval, lightly brush with oil, then fold in half crosswise. Cover bao with a damp cloth and let rise until slightly puffy, 60–90 minutes.

Place a bamboo steamer lined with parchment paper over a large pot of simmering water (or you can use a steamer basket). Steam bao in batches until firm to the touch and cooked through, 10–12 minutes per batch.

Cook sugar and soy sauce in a small saucepan over medium heat, stirring often, until sugar is dissolved; let cool.

Transfer to a small bowl and mix in chile, ginger, garlic, dark soy sauce, mushroom soy sauce, vinegar, and pepper. Let black pepper sauce sit 30 minutes to allow flavors to meld.

Build sandwiches with bao using turkey, black pepper sauce, mayonnaise, pickles, carrots, and cilantro.

Dough can be made 12 hours ahead; chill instead of letting rise. Let rise 2 hours. Bao can be steamed 1 week ahead; tightly wrap and freeze. Thaw and steam 3 minutes to restore softness just before serving. Sauce can be made 3 days ahead. Cover and chill.