Duck Confit Potpie

Name: Duck Confit Potpie
Ingredients: 3 medium sweet potatoes, peeled and cut into 1/2-inch dice; 1/2 pound cipollini onions, peeled and halved; 8 large garlic cloves, peeled; 5 thyme sprigs; 1 large rosemary sprig; 1/4 cup extra-virgin olive oil; Salt and freshly ground pepper; Buttery Cornmeal Pastry; 1 large egg, beaten with 2 tablespoons water; 1 large shallot, minced; 1/2 pound kale, stems and inner ribs discarded, leaves coarsely chopped (2 packed cups); 1/4 cup dry white wine; 3 cups chicken stock or low-sodium broth; 2 tablespoons all-purpose flour; 3 cups shredded Three-Pepper Duck Confit , see Note; 1/4 cup dried currants