In a food processor, combine flour, brown sugar, salt and cinnamon.  Add chunks of cold butter and pulse until crumbly.  Add in the oats and pulse a few times just to mix in (don’t over process so that the oats are ground up).  Set aside or refrigerate until ready to use.

In a large bowl, stir together the peach slices, 2 tablespoons brown sugar and cornstarch until coated.

Grill Method:   Spray four large squares of foil (or 4 small foil bowls) lightly with non-stick spray.  Divide peaches evenly onto foil squares.

Top each with some of the crumble mixture, then tightly seal the foil into packets. 

Place the packets on hot grill and cook until packets are steaming, the peach juices are bubbly and the crisp is slightly golden, flipping occasionally 15-20 minutes.  Cool slightly before serving. 

Oven Method/Foil Bowls: Divide peach mixture among 4 small foil bowls, sprayed with non-stick spray. 

Top each with some of the crumble mixture.  Transfer to preheated 350 degree oven and bake for 35-40 minutes.  They are done with the peaches bubbly and topping is browned. 

Let sit a few minutes, then serve with a scoop of vanilla ice cream, if desired.

Note:  Serves 4

You can make the topping ahead of time, transfer to a quart size Ziplock bag and freeze.  Thaw in refrigerator (may need to break up into small crumbles).