Place the pineapple, ginger, garlic, red pepper flakes, vegetable oil, soy sauce, and sesame oil into the bowl of a food processor and pulse until smooth.

Pour the marinade into a large resealable storage bag (I use the gallon size).

Add scallions and pork sirloin.

Seal the bag and massage pork until coated with the marinade.

Place the storage bag into the fridge and marinate for 1-2 hours.

(Turn the bag over every 30 or 45 minutes to ensure even distribution of the marinade).

Remove the bagged pork from the refrigerator about 20 minutes before you intend to cook it.

Preheat your grill (or grill pan) to medium heat.

Remove pork from marinade and gently shake off the excess marinade.

Grill for about 10 minutes on the first side.

Flip.

Grill 8—10 minutes on the second side, until the pork is cooked through.

Remove from grill and let rest for 5-10 minutes before carving.

Serve over rice.