• Preheat oven to 350°F (180°C). Line an 8-inch x 8-inch baking pan with parchment paper. Set aside.
• In a large mixing bowl, combine all the crust ingredients: oat flour, rolled oats, maple syrup, melted coconut oil, salt, and vanilla.
• Squeeze the batter with your hands to bring all the ingredients in contact and create a dough that sticks together. If too dry (may happen if you are using a coarse oat flour), add 1-2 tablespoons of water, add one at a time until the dough is soft and sticks together.
• Press roughly 1 cup + 2/3 cup of the dough all over the baking dish, using a spatula to smoothen the dough and making sure there is no hole left. Set aside leftover dough in a small mixing bowl in the fridge. It looks small but will be enough to finely crumble on top of the bar.
• Place the pan in the fridge while you make the apple filling.

Apple filling

• In a small saucepan, add the sliced apples, maple syrup, orange juice (or water), cinnamon, nutmeg.
• Cook for 2-3 minutes on medium heat, cover the saucepan, and stir often. Bubbles should form on the side of the pan.
• Stir in cornstarch and keep cooking on low heat for 2 minutes, stirring all the time to prevent the apples from burning. It should slightly thicken.
• Pour the apple filling on top of the prepared crust, then use the remaining dough to crumble all other the bar.
• Bake the bar for 35 minutes or until crispy on top and golden.

Peanut butter caramel

• Meanwhile, make the caramel. In a small saucepan, melt coconut oil with maple syrup and peanut butter over low-medium heat.
• Stir constantly until melted and combined and it looks like a caramel sauce.
• Set aside in a bowl or jar to cool and store at room temperature for up to 1 week in a sealed glass mason jar. If it becomes too thick to your liking, rewarm in the microwave for 20 seconds or in a saucepan before serving.

Cool the bars

• Remove the bars from the oven and cool in the pan 10 minutes before transferring onto a cooling rack.
• Cool for 3 hours or until it reaches room temperature before slicing into 16 bars. Waiting will prevent the bar from crumbling and the filling will set perfectly.

Serve and store

• Serve bar with a drizzle of caramel.
• Store the bars in the fridge in an airtight container for up to 1 week. Otherwise, freeze and defrost the day before breakfast.