Optional: Cinnamon and Powdered Sugar for sprinkling
Ingredients – Jam Filling
1 cup fresh blackberries
1 cup fresh raspberries
2 tbsp brown sugar
4 tbsp cornstarch (set entire amount aside in a bowl)
2 tbsp lemon juice
1/3 cup strawberry preserves
Directions
1) Preheat the oven to 350°F and line all sides with parchment paper. Lightly grease the pan and set aside.
2) Make the Crumble Dough: In a medium bowl mix together the flour, oats, brown sugar, baking powder, and salt until fully mixed together. Next pour in the melted butter and mix to combine. It should turn very crumbly but not too dry. Once done, press about 2/3 of the dough into the bottom of the baking pan, making sure to evenly distribute it amongst the entire bottom of the pan. Ensure the dough is tightly packed together (no noticeable breaks or holes), then bake for 10 – 12 minutes. The dough should looked slightly browned, but not fully cooked. While the dough cooks move on to the next step, and when the dough is finished baking place in the fridge until jam is ready (keep the oven on at the same temperature).
3)Make the Jam Filling: First set aside 5 -6 blackberries & raspberries each. In a medium bowl, add the remaining raspberries & blackberries, and brown sugar. Give the berries a rough mash with a fork, making sure to mash each berry a few times, about 2 – 3 minutes. Next mix in 1/3 of the cornstarch, lemon juice, and preserves. Mix everything together, once incorporated together add in another 1/3 of the cornstarch and mix, then add the final amount of cornstarch and mix again. The jam may look loose, but it will thicken when baking. Once ready, pull the prebaked dough out of the fridge.
4) Pour the filling over the prebaked crust, making sure to evenly distribute it across the layer. Scatter the whole berries set aside directly on top of the jam. Top with the rest of the crumble. If using cinnamon, sprinkle on top your preferred amount for flavor.
5) Bake for 30-35 minutes. The surface should look slightly darker and the edges will be a tiny bit bubbly and candied.
6) Allow the bars to cool at room temperature for about 90 minutes before slicing and enjoying. If using powdered sugar, lightly dust on top once cooled. Serve immediately while warm if desired. The bars can be stored in an air tight container in the refrigerator for up to 5 days.
