Preheat the oven to 350℉, and line a 9X15-inch pan with parchment paper and grease with oil spray. Set aside.
For this recipe, we need a food processor to grind the quick oats. The mixture will be quite powdery and light.
3 cups Quick oats
Add the flour, brown sugar, spices, and baking powder.
1½ cups All-purpose flour, 1½ cups Brown sugar, 1 teaspoon Cinnamon, ½ teaspoon Nutmeg, 1 teaspoon Baking powder
Add the cold butter and vanilla extract to the food processor and grind until the mixture looks broken and the butter turns into small pieces the size of a lentil. The mix is ready when you squeeze a small amount into your fingers; the mixture sticks together, and a cluster forms. If the mixture is too powdery and dry, add a small amount of milk to make it stick together.
1 cup Butter, 1 teaspoon Vanilla extract
Press half of this mixture onto the bottom of a lined 9X15-inch pan, and bake it for 15 minutes or until golden brown. Let it cool down.
How To Make The Berry Filling
In a large bowl, mix the berries. I mixed four kinds of berries, strawberries, raspberries, blackberries, and blueberries.
3 cups Mixed berries
Toss a couple of teaspoons of flour to coat them, then spread them over the base. Add in the brown sugar and vanilla extract and mix.
⅓ cup Brown sugar, 2 tablespoon All-purpose flour, 1 tablespoon Vanilla extract
Drop spoonfuls of each jam over the berries.
3 tablespoon Raspberry jam, 3 tablespoon Apricot jam
Drizzle the maple syrup over the berries.
2 tablespoon Maple syrup
Spread the remaining oat mixture all over the berries. If the mixture has small clusters, pinch some in your hand to make larger clusters. Bake it for 30 minutes, let it cool down in the pan for one hour, then transfer to the fridge for at least an hour before cutting.