Italian Banana Rooker Dessert! No oven, quick and easy!

Ingredients:
- 100g banana jelly powder
- 400 ml hot water
- 1 sliced ​​banana
- 700 ml milk
- 200g sugar
- 30g gelatin powder
- 40g corn starch
- 2 egg yolks
- 1/2 tsp vanilla
- 170g breakfast cream
- 50g chopped walnuts
- 50g crushed biscuits