I used Malcolm Reed's marinade as a baseline and modified it some...
Korean Beef Marinade
1 tsp Sesame Seeds
1 TBSP Ground Black Pepper
2 tsp Ground Ginger (or 2 TBSP fresh)
1/2 tsp Garlic Powder (or 3-4 cloves or 1-1/2 tsp minced)
1/2 tsp Onion Powder
1/4 Cup Dk. Brown Sugar (packed)
3 TBSP Sesame Oil
1/3 Cup Soy Sauce
1 TBSP (rounded) dried chives (or 3-4 green onion stems sliced fine)
2 TBSP Cider Vinegar
1-1/4 Cup Apple Juice (or water)
I like to wisk all ingredients together in a 4 cup size Pyrex pitcher.
Then pour and store refrigerated in a glass (preferably) container.
Yield = 2 cups
Marinate flanken style ribs 4 hours (refrigerated) then grill over direct heat to desired doneness.
Marinate longer for more soy taste, or bump up the soy sauce amount if desired.
Some comments on ingredients...
A traditional ingredient which does not seem to affect the marinade very much
1 TBSP seems like a lot but it works in this marinade
If you don't like much pepper, start with 1 tsp and work up
The soy sauce brings the salt and I didn't need any added
Add some (1/2 tsp) if you like a saltier taste
I don't like dealing with fresh, ground is easier
This along with the dried chives replaces the green onions
Easier, although hard to beat fresh
Dark brown sugar
Good amount for this recipe...not too sweet
An important flavor...I bumped it from 2 to 3 TBSP
Kadoya brand is very good
Another big player...I reduced it from 3/4 cup to 1/3 cup for better balance
Marinate longer for more soy taste, or bump up the amount if desired
Combined with the onion powder, an easy replacement for the green onions
4-5 full green onions seemed like a lot...I reduced it to 3-4 stems finely chopped when I use them
A strong player...I reduced it from 3 TBSP to 2 TBSP
Water or Coca-Cola is traditional but apple juice works very well
1-1/4 cups bumps the yield to an even 2 cups
Here are a couple of nice, wide QFC slabs about ready to plate.
For best flavor, try to keep flanken ribs away from any flare ups.