In a large non-reactive baking dish, place the pork loin.

In a medium bowl, combine the ginger ale, soy sauce, 1/2 cup of the sherry, honey, ginger, the onion, garlic, cardamom, and red pepper flakes. Pour over the pork, cover tightly and refrigerate 12 to 24 hours, turning occasionally.

Preheat the oven to 350 degrees F.

Remove the meat from the marinade and reserve. Pat the roast dry with kitchen towels, season lightly with salt and freshly ground black pepper, and place in a roasting pan. Cook uncovered until an instant-read thermometer registers an internal temperature of 155 degrees F, about 1 hour.

Remove the roast from the oven and place on a platter. Tent with aluminum foil and let rest for 10 to 15 minutes before carving.

Meanwhile, pour any remaining marinade into a medium saucepan and bring to a boil. Cook at a brisk simmer for 5 minutes. Place the roasting pan over 2 burners over medium-high heat. Add the remaining 1/2 cup sherry and cook, stirring to deglaze the pan. Pour the juices into the saucepan with the remaining marinade. Add the chicken stock and cook until reduced by almost half. Whisk in the butter and remove from the heat. Adjust the seasoning to taste. Strain into a sauceboat or decorative bowl.

To serve, arrange the sweet potatoes in the middle of the plate, the haricots verts to the side, and slices of pork around the top. Drizzle with the sauce and serve immediately.

Preheat the oven to 350 degrees F. Grease a large baking dish with the butter.

Toss the sweet potatoes in a large mixing bowl with the brown sugar, cane syrup, molasses, corn syrup, nutmeg, cloves, allspice, and cinnamon to coat evenly. Pour them into the prepared pan and roast until fork-tender, about 1 hour.