Dad's Flank Steak Marinade

1 cup Soy Sauce
1/2 cup Pineapple Juice
1/2 cup Brown Sugar
1/2 cup White Vinegar
2 te Salt*
1/2 te Garlic Powder

Bring above ingredients to a boil. Marinate at least 4 hours in refrigerator.
* I often omit the salt or cut it in half - the soy sauce and vinegar provide enough salt.

Notes:
The recipe is easily doubled.
Often I will make extra and throw it in a gallon freezer bag with a flank steak and freeze for a later date. Just bring the steak out of the freezer and let it thaw all day before throwing it on the grill.