Place all ingredients except the salt and kimchi in a stand mixer with the dough attachment. Start on low speed to allow the ingredients to mix. After a minute sprinkle in the salt (it can hinder the yeast if added too soon).
Turn the speed up to medium and allow the dough to kneed for several minutes until smooth.
Remove the dough and lightly oil the inside of the mixing bowl.
Place the dough back in the bowl, cover, and let rise for 60 minutes.
Deflate the dough and cut into 8 even pieces (start by cutting it in half, then those pieces in half, etc).
Use paper towels to drain some of the excess moisture from the kimchi so it doesn't saturate the dough.
Lightly oil an 8x8 or 9x9 cake pan.
To make the buns, stretch one piece of dough in your hands to about 4-5 inches in diameter, leaving the center a bit thicker. It should look like a large ravioli. You can press the edges with your fingers to help thin them out. You want the ends to be thin because they're going to overlap to create the bottom of the bun.
Place a tablespoon of kimchi in the center of the dough. Pull the ends over the kimchi and pinch the bottom together. Flip the bun over, gently reshape it into a proper circle if necessary and place in the cake pan. Repeat until you have 8 buns.
Cover the cake pan and allow the dough to rise for another hour.
Place squares of parchment in the bottom of a bamboo steamer. Lay out the buns and place the steamer over a wok or large sauce pot.
Steam the buns over simmering water for 25 minutes. Be careful when you remove them from the heat, the steam gets very hot!
To make the dipping sauce, whisk together all ingredients.