In a medium saucepan, over medium heat, bring the plums and maple syrup to a boil and simmer for 15-20 minutes. Remove from the heat when the plums are soft and allow to cool. Refrigerate until you are ready to use the filling.
Turn on the oven and preheat to 355 ˚F. Lightly grease and line an 8 inch x 8 inch cake pan.
Place the oats, almond meal, maple syrup, coconut oil, salt and cinnamon in a food processor. Process until the ingredients are fully combined and finely chopped.
Evenly press the base into the baking pan. Bake in the oven for 15 minutes. Allow to cool.
Spread plum filling evenly over the cooled base.
Mix the oats, almonds, pumpkin seeds, sunflower seeds, sesame seeds, flax seeds and coconut oil together in a bowl.
Sprinkle the oat and nut mixture over plum filling and press it in lightly.
Bake in the oven for 20 minutes until topping is golden and toasted.
Allow to cool completely.
Remove from pan and cut into bars or squares. Serve immediately or store in an airtight container in the refrigerator.
