Preparation With a sharp knife, score the skin of the duck breasts in a crisscross fashion. Put them in a large resealable plastic bag and pour in the marinade. Refrigerate overnight, turning the bag occasionally. Prepare a medium-hot fire in a grill. When the coals are ready, lightly oil the grill rack. Remove the duck from the marinade, allowing the excess to fall away, and place the duck skin side down on the grill. (Be careful, as dripping fat may cause the fire to flare up.) Grill for 6 minutes. Flip the breasts over and grill for an additional 7 or 8 minutes, or until medium-rare in the center. (If the duck begins to brown too much, move it to a cooler part of the grill to finish cooking.) Allow the breasts to rest for a few minutes on a platter. Rewarm the crema over low heat and spoon it onto six dinner plates. Cut each duck breast crosswise into thin slices and season with salt and pepper. Lay the duck slices atop the crema and serve. Recommended wine: A Malbec from Argentina to go with the tamarind in the barbecue sauce. Chef Norman Van Aken shares his tips with Epicurious: Reprinted with permission from New World Kitchen by Norman Van Aken. © 2001 HarperCollins Publishers, Inc.