We found this recipe in a cookbook named "Cooking with Foil", and, yes, it's a grill recipe. Most people would think that that was fabulous, but grilling is NOT my forte. And my husband could care less (probably has something to do with the fact that the grill master is relegated to a lonely messy garage while the party is going on inside the house). I made this recently for friends, and not wanting to tramp through the snow, I researched how to roast it instead. AND IT WAS INCREDIBLE. If I must say so myself. . .
Place pork loin in large resealable plastic food storage bag. Combine all remaining ingredients, except for the Spicy Yogurt Sauce, in small bowl; pour over pork. Seal bag and marinade in refrigerator overnight, turning bag occasionally.
Meanwhile, combine all of the Spicy Yogurt Sauce ingredients in a small bowl; blend well. Cover and refrigerate until ready to serve.
Prepare grill with rectangular foil drip pan. Bank briquets on either side of drip pan for indirect cooking. Remove pork, discarding marinade. Place pork on grill over drip pan. Grill, on covered grill, over low coals 1-1/2 hours or to an internal temperature of 155*F. Let rest 10 minutes. (Internal temperature will rise slightly upon standing.) To serve, thinly slice roast and serve with Spicy Yogurt Sauce.
Alternate roast method: Before marinating, slice off the silver-skin (see America's Test Kitchen for tips on how to do this). Before cooking, temper (bring to room temperature) and dry. Prepare a large fry pan by adding a tablespoon of olive oil and heating it over medium-high heat until the oil ripples and wisps of smoke rise. Sear the loin for 4 - 5 minutes per side. Place in a roasting pan and roast at 400* for 12 minutes. Properly cooked loin will have a slightly pink middle.