preheat oven to 350F
in a bowl, mix together 1 1/2 cup oats + 1 cup all purpose flour + 1 cup brown sugar + 3/4 cup softened butter until mixture is crumbly
press 2/3 of the mixture into a lined 9×9 dish
add 1/4 cup peach butter or peach jam on top
dice 1 peach into small pieces and sprinkle evenly on top
crumble remaining mixture over peaches
bake for 30-35 min or until golden
let cool for 2 hours to fully set into bars or cut immediately if you want warm crisp like texture