In a large pot, combine water, fish sauce, garlic, green onions, and onion. Bring to a boil over high heat.
Once boiling, reduce heat to medium-low and simmer for 20 minutes to create a flavorful broth. Strain the broth and discard the solids.
Return the broth to the pot and bring it back to a boil. Add the sliced rice cakes and cook for about 5 minutes until they float to the top and are soft and chewy.
Add the beef slices to the pot and cook for an additional 2-3 minutes until no longer pink.
Season the soup with soy sauce, sesame oil, salt and pepper to taste.
Slowly drizzle the beaten eggs into the pot while stirring gently to create egg ribbons.
Ladle the hot soup into bowls and garnish with crumbled seaweed and chopped green onions. Serve immediately.
Notes
Recipe Tips
Look for pre-sliced rice cakes at Korean grocery stores for convenience
Freezing the beef for 30 minutes makes it easier to slice thinly
Vegetarian option: Use a kombu-mushroom broth instead and omit the beef
Add gochugaru (Korean red pepper flakes) for a spicy kick
For a richer broth, use beef stock in place of some water
Cook rice cakes until very soft for an authentic texture
Serving Suggestions
Serve Duk Guk piping hot as a comforting meal, especially during colder months. This soup is often enjoyed as a breakfast or lunch dish.
Serve with:
Kimchi
Stir-fried vegetables
Glass noodles (japchae)
Vegetable pancakes (pajeon)
Variations
Add sliced mandu (Korean dumplings)
Use chicken broth and chicken instead of beef for dakguk
Include diced potatoes or sweet potatoes for added texture
Top with a soft-boiled egg instead of egg ribbons
Make it spicy by adding gochujang (Korean red pepper paste) to the broth
Storage
Store any leftover Duk Guk in an airtight container in the fridge for up to 3 days.
The rice cakes will continue to absorb the broth and soften.
Reheat gently in a pot over medium heat until warmed through, adding more broth or water if needed to thin it out.