Rum and pineapple marinade

Nick sent us his favourite marinade recipie … a Rum and pineapple marinade. Delicious!
1/2 cup pineapple juice (fresh is better)
1/3 cup rum (Jamaican rum works best, never tried dark rum though)
1/4 cup soy sauce
2 tablespoons brown sugar
1 tablespoon ginger, grated
2 cloves garlic, minced
1/2 teaspoon red pepper flakes, crushed

Combine and let steaks marinade for 3-4 hours in the fridge. Do not marinade for more than 4.