Finale-style courgettes with ham

Wash the courgettes and cut them in half lengthwise. Steam them or boil them in a pan of salted water for 8-10 minutes, until they are tender but still slightly crunchy. Listen and let them cool.
Preparation of the ham rolls:
Roll each courgette half in a slice of ham and arrange them on a pre-buttered gratin dish.
Bechamel preparation:
If you are making a homemade béchamel, melt the butter in a saucepan, add a tablespoon of flour, then gradually pour in the milk, stirring until the sauce thickens. Salt, pepper and add a pinch of nutmeg if you like.
Pour the béchamel over the courgette and ham rolls in the gratin dish.