Croissant Chocolate and Banana Cake

Name: Croissant, Chocolate and Banana Cake
Ingredients: 8 all butter croissants; 2 bananas, cut into 1/2 centimeters slices; 200 grams milk and dark chocolate chunks; 1 tablespoon demerara sugar; 200 milliliters double cream; 170 milliliters full milk; 2 teaspoons vanilla extract; 3 large whole eggs; 70 grams caster sugar