Combine blueberries and maple syrup in a saucepan over medium heat. Warm the berries for 5-10 minutes (depending if fresh or frozen) to draw out their liquid. Heat to boiling and stir every so often as the berry liquid begins to thicken.
Next, add in the chia seeds and stir to combine. Heat for another 3-5 minutes and then remove from heat. The longer the ‘jam’ sits the thicker it will become.
for the oat bars:
Heat oven to 375 F. Line an 8×8 baking dish with parchment paper, leaving some excess on the sides so you can easily lift the bars up when finished baking.
Using a food processor, pulse 1 cup of the rolled oats until it becomes a smooth flour. In a mixing bowl combine the new oat flour, remaining 1 cup of rolled oats and baking powder.
Add the mashed bananas, vanilla extract and maple syrup into the oat mixture and stir to evenly combine. This mixture becomes the ‘dough’ for the oat bars.
Spread 2/3 of the ‘dough’ on the bottom of the baking dish. Top with the blueberry jam mixture and evenly spread, keeping 1/4 inch of the jam away from the edge of the dough to prevent burning. Add the remaining oat dough on top of the jam and spread to coat.