01 - Preheat the oven to 350°F. Line an 8x8-inch baking pan with parchment paper.
02 - In a medium bowl, toss diced pears with maple syrup, cinnamon, lemon juice, and cornstarch until evenly coated. Set aside.
03 - In a large bowl, combine rolled oats, whole wheat flour, brown sugar, cinnamon, and salt. Pour in melted butter and vanilla extract. Stir until the mixture is crumbly and evenly moistened.
04 - Reserve 3/4 cup of the oat mixture for the topping. Press the remaining oat mixture firmly and evenly into the bottom of the prepared pan to create a solid crust layer.
05 - Spread the pear mixture evenly over the pressed oat crust, ensuring it covers the entire surface.
06 - Sprinkle the reserved oat crumble evenly over the pear filling, covering it completely.
07 - Bake for 35 minutes, or until the top is golden brown and the fruit filling is bubbling around the edges.
08 - Allow the bars to cool completely in the pan before cutting into 12 bars. This ensures clean edges and proper set.