Cut rhubarb into 1-inch pieces. In slow-cooking pot, combine rhubarb with
3/4 cup sugar, cinnamon, cloves, and grated peel. Cover and cook on low
for 3 to 4 hours. Remove cinnamon and cloves. Spoon rhubarb into shallow
baking dish. In small bowl, mix together butter, flour and 1/3 cup sugar
with fork or pastry blender. Sprinkle over cooked rhubarb. Bake in 400 F
oven for about 20 minutes.