Yes, you can. I use that exact same sauce for my bulgogi bowls. I add garlic, very little ginger, and pepper to the sauce. I also sauté some onions. Give it a try, it's really good!

You could, but it won't be "korean" if youre using a "japanese" sauce. Try it out and see how you like it though! I've never tried this particular japanese bbq sauce, but the ingredients are somewhat similar to the recipe.
I often make a similar dish, sometimes using shaved beef but ground beef is a quick and easy sub. I add regular onions to cook (instead of just green) and serve over rice.

Close enough, but it might be too thick. Many places stock a bulgogi marinade.

Instead of using individual ingredients?

https://damndelicious.net/2013/07/07/korean-beef-bowl/


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