Mix spelt, semolina, 40 g cinnamon, vanilla pulp, nut flakes and lemon zest. Add the liquid butter and honey. Knead everything together until crumbly. Remove peel from apples, cut into quarters and remove core (set aside 1 apple quarter, drizzle with a tiny bit of juice from one lemon).
Coarsely grate apples. Peel bananas (set 1 banana aside), cut into slices. Mix fruit and casserole mixture. Fill into a greased ovenproof dish and bake at 200 °C for about 30-40 minutes. After 20 minutes, top with apple slices and banana halves. Sprinkle with remaining nuts.
Serve with vanilla sauce.