Pour 2 cups of room temperature, unpasteurized makgeolli into a pot.

Add sugar or a zero-calorie sweetener to the makgeolli and stir until dissolved.

Gently heat the mixture over low heat for about 30 seconds until lukewarm (around 104°F or 40°C), then turn off the heat.

Sprinkle the active dry yeast over the warm mixture and let it sit for 1 minute.

Add the all-purpose flour and salt to the pot.

Mix with a spatula until the batter is smooth and well-combined, without any lumps.

Cover the pot and let the dough ferment in a warm place for about 2 hours until it has risen and is full of bubbles.

Check the fermented dough after 2 hours; it should be bubbly and risen.

Prepare your steamer by lining the basket with a wet cotton cloth. Place a cake ring inside if you have one.

Pour the fermented dough into the prepared steamer basket and spread it evenly.

Sprinkle fresh beans over the top of the dough.

Dice half an apple into small pieces and sprinkle them over the dough.

Let the dough rest for another 30 minutes. In the meantime, boil water in the bottom of your steamer.

Place the steamer basket over the boiling water, cover, and steam for 35 minutes over medium-high heat.

After 35 minutes of steaming, carefully remove the lid.

Lift the bread out of the steamer using the cotton cloth and place it on a cutting board.

Remove the cake ring (if used) and carefully peel off the cotton cloth.

Flip the bread over, peel off the silicone mat and remaining cloth, then flip it back.

Let the bread cool slightly, then cut it into your desired serving pieces.

Serve and enjoy your fresh, fluffy Sulppang.