Preheat your oven to 350°F (175°C). This ensures your granola bars bake evenly and achieve that perfect chewy texture.
Line your baking pan with parchment paper, allowing some overhang on the sides for easy removal later.
In a large mixing bowl, combine the oat flour, baking powder, baking soda, salt, and ground cinnamon. Whisk these dry ingredients together until well incorporated.
In another bowl, beat the room temperature butter and brown sugar together until light and fluffy, about 2-3 minutes.
Add the egg, honey, unsweetened apple sauce, and vanilla extract to the butter and sugar mixture. Mix until combined.
Gradually add the dry ingredients to the wet mixture, stirring until just combined. Avoid overmixing.
Gently fold in the quick oats, dark chocolate chips, raisins, and chopped pecans until evenly distributed.
Pour the granola mixture into the prepared baking pan. Use a spatula to spread evenly and press down gently to compact the mixture.
Bake for 20-25 minutes, until edges are golden brown and center is set.
Remove from oven and let cool in the pan for about 10 minutes. Lift bars out using parchment overhang and cool completely on a wire rack before cutting.