Start by preheating the oven to 350 degrees
Line the bottom of an 8×8 pan with parchment paper leaving some overhang, set aside
Begin with making the crust, crumble topping:
In a large bowl add the flour, oats, honey, brown sugar, ground cinnamon and salt
Mix until combined
Then, add the melted butter and vanilla stirring until mixture starts to combine
Now, use your hands and kneed until combined
Your mixture will be a little dry and crumbly which is good
Set aside 1 cup of the mixture, this is the crumble topping
Grab the rest of the oat mixture and add it to the baking pan lined with parchment paper
Now using your hands, press the oat mixture into the bottom of the pan
Make sure that the oats layer is even
In a medium bowl, combine the blueberries, lemon, sugar, and corn starch
Stir until the blueberries are coated well
Next, add the blueberries over the crust in an even layer
Grab the 1 cup of oat mixture you set aside
Crumble the oat mixture over the top of the blueberry layer
Bake at 350 degrees for 45 minutes, check randomly to make sure your bars aren't burning
Remove the bars from the oven when time is up and set aside for 10 minutes to allow the bars to cool
Lastly, cut and enjoy!