Blackened Barbecued Pork Fillets

This is from Jamie Oliver's Cook with Jamie. Pretty easy, and really tasty.

Ingredients:

1/4 tsp. cumin seeds
1/2 tsp. fennel seeds
1 clove
1/2 heaped tbsp. sweet smoked paprika
Zest and juice of 1/2 orange (see note)
Small bunch of fresh thyme, leaves picked and very finely chopped
2 garlic cloves, peeled and very finely chopped
1/3 cup plus 1 tbps. ketchup (half of 3/4 cup total)
3 tbsp. balsamic vinegar
2 pork loins
Kosher salt and freshly ground pepper
Optional: 1/2 handful of fresh cilantro, leaves picked and chopped
Optional: juice of 1/2 lemon

Making the Marinade:

Crush up the cumin, fennel seeds and clove in a pestle and mortar and mix with the paprika, orange juice, thyme, garlic, ketchup and balsamic vinegar. (I would recommend leaving out the orange zest.) Season the pork loins with salt and pepper, then toss them in most of the marinade until compeletely coated, reserving enough marinade for basting. Marinate at least an hour, up to a half a day.

Cooking:

Grill the meat on a barbecue or place it under a hot broiler for 15-20 minutes or until nicely charred. Brush the meat with the leftover marinade every time you turn the meat so you build up a sticky, blackened glaze. When they're done, put them on a platter to rest for 5 minutes. Slice the meat thickly and optionally sprinkle with chopped cilantro or squeeze with lemon juice "if you fancy." I skipped that and served with Tony Roma's barbecue sauce for dipping.