01 -
Get your oven warming to 375°F (190°C) and line an 8-inch square pan with parchment paper, leaving extra hanging over the sides for easy lifting later.
02 -
Combine your oats, flour, brown sugar, baking soda, salt, and cinnamon in a bowl until well mixed. Pour in the melted butter and vanilla, stirring until you've got a nice crumbly mixture.
03 -
Take half of your crumbly oat mixture and press it firmly into your lined pan, making sure it's even and well-packed.
04 -
Toss your blueberries with the granulated sugar and cornstarch until they're evenly coated. Spread this mixture over your pressed oat base.
05 -
Sprinkle the remaining oat mixture over your blueberries, giving it a gentle press to set it in place.
06 -
Let it bake for 35-40 minutes until you see golden brown peaks and bubbling blueberries. Cool completely before lifting out with the parchment paper and cutting into squares.