In a small saucepan, mix 2 tablespoons of cornstarch with 1/2 cup water to create a water roux, heating until thickened; set aside.

In a mixing bowl, combine 1 cup of heated milk, 2 teaspoons of instant yeast, 2 tablespoons of sweetened condensed milk, 3 cups of all-purpose flour, and 1 teaspoon of kosher salt. Knead the mixture for about 10 minutes until the dough is smooth and elastic.

Once kneaded, shape the dough into a ball and place it in a lightly oiled bowl. Cover and let it rise in a warm place for about 1 to 2 hours, or until doubled in size.

While the dough is rising, prepare your desired fillings. For a savory option, mix together 1 cup of finely shredded cabbage and 1/2 cup of ground pork in a bowl; season with salt and pepper. For a vegan filling, stir together 1 cup of crumbled tofu, 2 tablespoons of miso paste, and 1/2 cup of chopped carrots.

After the dough has risen, punch it down gently and divide it into equal pieces. Roll each piece into a small circle, spoon in 1-2 tablespoons of filling, pleat the edges together, and securely seal the buns.

Place the shaped buns on a steaming rack lined with parchment paper, cover with a damp cloth and let them proof for about 30 minutes.

In a large pot, bring water to a simmer, set the steaming rack with proofed buns over the pot, and steam for about 10 minutes.

Your delightful homemade steamed buns (baozi) are now ready to be enjoyed! Serve warm with soy sauce or chili oil.