Sweet Potato Tart

Name: Sweet Potato Tart
Cuisine: American
Ingredients: ½ egg white; 1 cup pecan halves, broken lengthwise; 2 pounds sweet potatoes, peeled and quartered (about 3 cups); ¼ teaspoon ground ginger; ¼ teaspoon ground cinnamon; Pinch of ground cloves; 2 egg whites; ⅓ cup sugar; 1 recipe Pie Dough, made with butter and prebaked in an 11-inch tart pan (see Basics); 1 recipe Pie Dough, made with butter and prebaked in an 11-inch tart pan (see Basics); 1 recipe Pie Dough, made with butter and prebaked in an 11-inch tart pan (see Basics); 16 crystallized violets, for decoration; Whipped heavy cream, for serving