In a bowl, combine all the ingredients. Set aside.
On a work surface, with a paper towel, remove the white membrane on the back of the ribs. Place the ribs on a baking sheet and sprinkle generously with the dry rub, rubbing the meat well on both sides. Cover and refrigerate for 1 hour or overnight.
With the rack in the middle position, preheat the oven to 170 °C (325 °F).
Wrap the ribs, up to two racks at a time, in aluminum foil. Place on a baking sheet. Bake for about 2 hours or until the meat is tender.
Meanwhile, in a saucepan, fry the spices in the butter for 1 minute and add the remaining ingredients. Bring to a boil and simmer for about 5 minutes or until the sauce is syrupy. Season with salt and pepper.
Preheat the grill, setting the burners to medium. Oil the grate.
Unwrap the ribs and grill for about 4 to 5 minutes per side, basting with half the sauce. Keep the remaining sauce for service.