In a container (in which you can cook custard), mix the egg, sugar and starch, add the milk and put it on the fire. With constant stirring, bring to a boil. When boiling, the mixture will thicken. Add the butter directly to the hot water. Leave to cool.
Grind cookies and hazelnuts in a meat grinder. You can use any other nuts. Cut the banana randomly. We use the caramel sauce purchased or you can prepare it yourself (there are not bad recipes on the site).
We collect our dessert, adding a teaspoon: a mixture of cookies with nuts, custard, bananas, caramel sauce, and so on until the glass is filled.
From this number of products, I got 6 glasses of 150 ml each.