This sweet and savory flank steak marinades in a combination of pineapple juice, soy sauce, brown sugar, ginger, and garlic for a delicious grilled dinner!
Whisk together all ingredients except steak until combined. Remove ¼ cup and set aside.
Score flank steak with a knife diagonally on both sides. This just means to run a sharp knife through it in the pattern below. You don't want to actually cut through the steak, just about ⅛" deep. This will help tenderize the meat.
Place steak in large zip-top bag and pour marinade (excluding the ¼ cup you set aside) over it. Refrigerate 8 hours or overnight. Take out of fridge 30 minutes before grilling.
Preheat grill to medium heat. When hot, place steak on grill and cook for 5-10 minutes per side, depending on the size. Use the ¼ cup marinade you set aside to brush over steak in the last few minutes of grilling. Flank steak should still be pink in the middle when done.
Remove from grill and let stand for 5 minutes before cutting so the juices can redistribute. Thinly slice against the grain and serve immediately.
Notes
Broiler Instructions: The other way to cook a flank steak is under the broiler (please don't anyone just pop it in a frying pan. Not good.) Place on a broiler pan on the upper rack and broil for about 5-10 minutes per side depending on the size. Because this particular marinade has sugar in it, you'll want to watch carefully so it doesn't burn. If you see the sugar burning too much, then you might want to move your rack down.
This flank steak is delicious eaten right away, but it makes great leftovers as well! Store leftover meat in the refrigerator in an airtight container or tightly wrapped in foil and eat within 3 days for best flavor. I love it cold on salads or chopped into bite sized pieces on a sandwich with toasted sourdough.
Don't skip the resting period after your flank steak is pulled off the grill! This rest is important for juices to redistribute through the meat. If you cut right in after cooking, you'll see all of those beautiful, flavorful juices run right out of your meat onto your cutting board!