Endives and Ham with Gruyere

Name: Endives and Ham with Gruyere
Ingredients: 1 1/2 cups fresh breadcrumbs (from about 1/3 loaf ciabatta or sourdough bread, crusts removed); 2 teaspoons extra-virgin olive oil; 8 Belgian endives, cored if desired; 1 tablespoon sugar; Coarse salt and freshly ground pepper; 6 ounces smoked ham, such as Black Forest, or jambon de Paris, sliced 1/4 inch thick; 1 teaspoon chopped fresh thyme; 1/3 cup homemade or store-bought low-sodium chicken stock; 1 cup grated Gruyere cheese (about 2 ounces); 1 ounce (2 tablespoons) unsalted butter, cut into small pieces, plus more for dish