In a large mixing bowl, combine flour, caster sugar, salt, and yeast. Gradually add warm milk and water, along with melted butter. Mix until a sticky dough forms, then knead for about 10 minutes until smooth and elastic.

Transfer the kneaded dough into a greased bowl, covering it with a damp cloth. Let it prove in a warm space for approximately 90 minutes, until it has doubled in size.

Once the dough has risen, punch it down gently to release the air. Divide the dough into 20 equal pieces and shape each into an oval. Lightly brush each piece with olive oil.

Using a chopstick, place it vertically in the center of each oval and fold the dough around it to create a pleated bun shape. Let them prove for another hour.

Marinate chicken breasts in buttermilk for at least 1 hour, seasoning with salt, pepper, and garlic powder.

Remove chicken from buttermilk and dredge each piece in seasoned flour. Deep-fry the chicken until golden brown and crispy.

In a saucepan, combine gochujang, honey, brown sugar, and soy sauce. Add minced garlic and ginger, then simmer until thickened.

Prepare a steamer and steam the bao buns for 10 minutes until soft and slightly sticky.

Fill each bun with crispy chicken and drizzle with gochujang glaze. Optionally add garnishes.