Preheat oven to 350°F. Line an 8” x 8” baking pan with parchment paper.
In a large bowl, blend coconut oil, sugar, and egg together with a stand mixer or handheld beaters on medium high until combined.
Add all-purpose flour, oat flour, cinnamon and salt, blending on low until just combined.
Press mixture into prepared pan. Pat into an even layer. Chill in fridge for at least 20 minutes while preparing remaining layers.
Make filling
Toss the diced strawberries with sugar and lemon juice. Set aside.
Make crumble topping
In a large bowl, combine the flours, coconut oil, sugar and salt.
Add the rolled oats and toss with your fingers until well mixed and crumbly.
Assemble
On the chilled base, spread an even layer of the strawberry mixture.
Sprinkle the crumble on top of the strawberries as evenly as possible, but do not press down.
Bake for 45-50 minutes, or until golden on top and strawberries are slightly bubbling at edges.
Cool in pan for at least 20 minutes before removing. Allow to cool completely before slicing into 9 squares.
Video
Notes
Storage: Store the oat bars in an airtight container in the fridge for up to 4 days. It will not be as crisp but can be reheated in the oven to make more crisp.