1cinnamon stick, about 2 inches long (use Ceylon or true cinnamon if you can)
1/2teaspoonkosher or sea salt, or more to taste
6duck breasts with skin, about 6 to 8 ounces each
1teaspoonkosher or sea salt, or more to taste
1/2teaspoonblack pepper, freshly ground, or to taste
Pour concentrate and broth into a medium-sized heavy saucepan over medium high heat. Bring to a boil and add the orange rind, bay leaf, cloves, peppercorns, cinnamon stick, vinegar and salt. Simmer at medium-high heat for about 35 minutes.
Bring heat down to medium-low, as the sauce will have reduced considerably and will be simmering too strongly. Keep on a low simmer until the sauce achieves a thick, syrupy consistency, about 10 more minutes. Don't let it thicken too much, as the sauce will continue to thicken as it cools. Remove the spices using a slotted spoon or strainer, and reserve in a container.
If you are not going to use it in the next couple of hours, or you made more than you need, let it cool, cover and refrigerate. Reheat before using.
Thoroughly rinse the duck breasts under a thin stream of cold water and pat dry. Make 6 to 8 diagonal cuts through the skin of each breast, being careful not to cut through the meat. Season with kosher salt and pepper to taste.
Preheat the oven to 400°F.
Heat a heavy skillet over medium-high heat. Once it is hot but not smoking, place the duck breasts skin-side down and sear for 6 to 7 minutes, until the skin is brown and crisp, and most of the fat melts and turns into liquid.
Move the breasts, skin-side up, to an ovenproof dish or pan. Place in the oven for 5 to 9 minutes, depending on how rare you like your meat: about 5 minutes for quite rare and about 8 to have a nice pink center.
Remove the breasts from the oven and let them sit for a couple of minutes before slicing. Slice diagonally along already marked skin. Drizzle jamaica and orange sauce on top.