Combine all the marinade ingredients in a bowl and add the pork belly. Let marinate for at least 30 minutes, up to 2 hours.
Heat a Dutch oven over medium heat and add 1 tablespoon cooking oil.
Cook the pork belly until browned and cooked through, about 3-4 minutes per side. (You'll need to cook it in 2 batches).
Remove the pork belly and set aside.
Add the remaining ingredients (except toppings) and bring to a simmer for 10 minutes.
Strain and serve in bowls over noodles with toppings and pork belly slices.
Notes
For quick and even browning, you’ll want to cook the pork belly in a single layer. Depending on the size of your Dutch oven, this means cooking it in at least two batches.
If you’re adding soft boiled ramen eggs as a topping, I recommend making them in advance as they need to marinate overnight.
If you think you’ll have leftovers, be sure to store the noodles, pork belly and broth separately. If combined, the noodles will soak up the broth and get mushy.
To control the saltiness of your ramen, I recommend using a homemade or low sodium chicken broth.
If you’re not a fan of spicy flavor, just reduce the amount of gochujang you use.
I don’t recommend substituting for the gochujang and doenjang. They’re absolutely necessary for the authentic Korean flavors. Check out this post to learn a little more about essential Korean ingredients.