Pear Crisp

Ingredients 6  cups  Anjou or Bartlett pears, cored and cut lengthwise into 1/2-inch-thick slices (about 3 pounds) 1  tablespoon  fresh lemon juice 1/3  cup  rapadura (or your choice of sugar) 1  tablespoon  cornstarch 1 1/2  teaspoons  ground cinnamon, divided 1/3 ...