Preheat the oven to 350 degrees. Grease a 9 x 13 baking dish with 2 tablespoon butter. This will be a thick coating of butter, which is good, it will add to the flavor of the dish:-)

In a medium bowl, combine all of the ingredients for the crumble topping except the butter. Mix with a large spoon or spatula until the dry ingredients are evenly combined.

Slowly add the melted butter while stirring to combine until it looks like damp sand, but isn’t wet. Large crumbles will likely form which is great. You may not need all of the butter. Set the mixture aside while you work on the filling.

Rinse, peel and cut the peaches into large chunks. Place in a large bowl. Add vanilla to the peaches.

Combine sugar, cornstarch and cinnamon in a small bowl. Sprinkle the peaches with the sugar mixture. Gently mix together with a large spoon until the peaches are evenly covered with the sugar mixture.

Pour the peach mixture into the prepared baking dish. Sprinkle the crumble mixture on top and spread out evenly. Bake for 45 minutes. Check around 30 minutes into the cooking time and if the top is becoming brown, cover it loosely with aluminum foil and continue baking for the full 45 minutes.

Remove from the oven and serve warm or at room temp with whipped cream or ice cream if you wish.