How to Make It
Preheat the oven to 425°. On a large rimmed baking sheet, toss the sweet potatoes with the onions, garlic, thyme, rosemary and 3 tablespoons of oil. Season with salt and pepper. Cover with foil and roast for 30 minutes, stirring once or twice, until the vegetables are tender and lightly browned on the bottom. Remove from the oven and set aside the garlic. Discard the herb sprigs. Reduce the oven temperature to 375°.
On a lightly floured work surface, roll out the Buttery Cornmeal Pastry to a 14-inch round, about 1/8 inch thick. Using a 5 1/2-inch plate as a template, cut out 4 rounds as closely together as possible. Roll out scraps and cut out 2 more rounds. Set the rounds on a baking sheet lined with parchment paper. Brush with the egg wash and freeze for 5 minutes. Bake the rounds for about 15 minutes, until golden and crisp.
Meanwhile, heat the remaining 1 tablespoon of olive oil in a large deep skillet. Add the shallot and cook over moderate heat until softened, about 3 minutes. Add the kale and cook, stirring, until wilted, about 2 minutes. Add the white wine and cook until nearly evaporated. Add 2 1/2 cups of the chicken stock and bring to a simmer.
In a small bowl, whisk the flour into the remaining 1/2 cup of chicken stock, then whisk the mixture into the skillet. Simmer until slightly thickened, about 5 minutes. Mash the roasted garlic cloves and whisk them into the sauce. Add the roasted vegetables, duck confit and currants and cook until heated through; keep warm.
Ladle the duck filling into six 1-cup ramekins, cover with the pastry rounds and serve at once.
You can use the meat from 5 confited duck legs instead of making your own. They're available, along with pure duck fat, from D'Artagnan at dartagnan.com or 800-327-8246.