Use a sharp paring knife to cut each peach in half. Remove the pit from the center
Heat the butter, brown sugar, and vanilla in a large skillet over medium heat. Stir frequently to prevent burning until the butter is completely melted and turns a soft brown color.
Once the butter mixture begins to bubble, place each peach half, flesh side down, into the pan. Place the lid on top of the pan so the peaches stay nice and juicy.
Allow the peaches to simmer in the butter mixture until the edges have caramelized. You can gently flip one over to check the doneness of the peaches.
In the same pan, add the oats, oat flour, cinnamon, and another 1 Tbsp of butter. Mix the oat mixture together in the pan with a spatula and allow the oats to cook until small clumps begin to form
Serve each peach half with a scoop of ice cream on top followed by a little bit of the toasted oat crumble.