A rub, sometimes referred to as a dry rub, draws a portion of the juices from a cut of meat to the surface, there to mingle with the seasoning and with it form a crust encasing the rest of the meat's juices and flavor. The secret to concocting a good rub lies in not skimping on the ingredients. The mix must be ample enough to coat the meat completely, sealing it in spices. One way to help achieve this objective is to dump both rub and ribs into a Ziploc-type plastic bag and shake the bag until the ribs are well covered with the seasoning. The bags designed for the freezer are a bit stronger than the regular storage ones, and I recommend this sturdier version for the aforesaid activity. Nothing spawns a sneeze storm quite as spectacularly as the sudden ripping of a gyrating bag full of peppery ribs.

For the rub, measure the brown sugar into a small mixing bowl and mash out any lumps with a fork. Add the paprika, garlic powder, and cayenne, black, and white peppers, followed by the coriander and salt. Blend these ingredients well and pour into a Ziploc-type plastic bag large enough to hold the ribs comfortably. Add the ribs and shake the bag until they are thoroughly dusted with the rub. Refrigerate, tightly closed, overnight. Shake the bag once before going to bed and again in the morning.

About 5 1/2 hours before you plan to serve the ribs, fire up your smoker and start putting the mop together. For the mop, melt the butter in a medium-size stainless steel or flameproof ceramic saucepan set over low heat. Stir in the onion and garlic and saute gently until golden. Add the tomato paste and mix well. Blend in the vinegar, water, and molasses. Add the brown sugar, Worcestershire sauce, and, a little at a time, the chili powder and dry mustard, stirring well after each addition. Simmer, stirring occasionally, for about 30 minutes, or until the sauce is thick. Remove from the heat and set aside until needed for basting.

Once the fire in your smoker has settled down to a good bed of coals that will last for a number of hours without too much tending, add a few chunks of wet wood or chips and put the ribs on the grill over a pan of hot water. Let smoke, covered and undisturbed, for about 2 hours. At that point, open the smoker lid and baste the ribs well with the mop, taking this opportunity to check the coals in the fire pan and the liquid level in the water pan. Replenish as needed, adding wet wood for plenty of smoke as well.

Cook the ribs for 3 hours more, turning and basting them after 1 hour and again after 2 hours. As always in smoke cooking, precise timing is not terribly important here. Just keep the smoke up and the temperature at 200 to 240 degrees F. and be liberal with your mopping. By the end of their 5 hours on the grill, the ribs will have long since reached and passed the internal temperature of 160 to 170 degrees F. recommended for pork. But you can't overdo ribs by smoking, and the long, slow cooking will have rendered them tender to a tee.