To Prepare the Filling

1. Preheat oven to 350 degrees F.
2. Bring a pot of water to a boil over high heat; make a shallow "X" in the bottom of each peach using a paring knife
3. Once the water is boiling, drop 4 peaches at a time into the water, let sit for 40 seconds, then carefully remove using tongs and place in an ice bath; repeat with remaining 4 peaches. Allow all the peaches to dry on paper towels.
4. When peaches are cool enough to handle, use a paring knife to remove the skin from the peaches, starting at the "X" on the bottom.
5. Halve peaches and remove the pit; slice peaches into 1/2 inch slices.
6. Combine the peach slices, vanilla, cinnamon and sugar in a medium bowl, set aside.

To Prepare the Topping

1. Place 1 package of graham crackers in a resealable plastic bag and crush into small pieces, using a rolling pin; place the graham cracker crumbs into a medium bowl.
2. Add oats, flour, brown sugar, baking powder and salt to the graham cracker crumbs, stir to combine.
3. Add cold butter cubes; using fingers, cut butter into dry ingredients until large crumbs form.

To Assemble the Crisp

1. Grease a 9x13-inch glass baking dish
2. Pour peach mixture into greased baking dish; sprinkle prepared topping evenly over peaches.
3. Bake crisp at 350 degrees F for 45 minutes, or until fruit is bubbling and topping is brown. Serve warm with vanilla ice cream.