Nectarine Crisp

4 1/2 lbs ripe nectarines, sliced (about 12)
2 cups uncooked quick oats
1 1/4 cups packed brown sugar
2/3 cup flour
2/3 cup cold butter, cut into small pieces
1/8 teaspoon cinnamon
1/2 gallon vanilla ice cream (optional)

Heat oven to 350º. Lightly grease a 13x9 baking dish.
Arrange sliced nectarines in prepared baking pan.
Mix oats, brown sugar, and flour. Cut in butter with pastry blender or rub in with fingertips until mixture is crumbly.
Sprinle over fruit.
Dust with cinnamon.
Bake 30 to 35 minutes or until fruit is soft and topping is crisp and browned.
Serve warm with vanilla ice cream if desired.