To make the crumble layer, mix together all the dry ingredients in a large mixing bowl. Once well-combined, add in the wet ingredients and mix with your hands until the crumble mixture comes together. Place to the side whilst you make your fruit base.
Chop up your apples into small chunks, discarding the core. Place in a saucepan along with the sachet, berries and maple syrup. Allow to simmer on a low-medium heat for about ten minutes, until the fruit has softened, but isn’t mushy.
Transfer this fruit mixture to the bottom of a baking dish and layer with the crumble topping. Bake for 20-30 minutes until the top is golden brown. Serve and enjoy with a vegan custard, cream, ice cream or even just on its own!