Preheat oven to 190 degrees C (fan-forced) and line a 9x9 baking tin with baking paper.
Add the oats to a food processor or blender and pulse a few times to achieve a rough meal texture. Add remaining oatmeal crust ingredients to the blender and combine until a moist crumbly dough forms (add a dash more maple or peanut butter if it's too dry to hold together.) Press mixture into the base of the baking tin.
In a blender or food processor, blend the lemon curd ingredients together until smooth. Pour the curd onto the oatmeal crust and bake for 40-45 minutes or until the edges start to turn golden brown.
Allow the lemon bars to cool at room temperature (atleast an hour or so.) Transfer to an airtight and place in the refrigerator overnight to set (if time allows) before cutting into bars and enjoy!