Start by cooking pasta in a pot of simmering water according to package directions.
Meanwhile, preheat the oven to 200°C. Then peel the shallot before slicing it. Heat 1 tablespoon oil in a frying pan and fry the shallots. Book.
Continue cooking the bechamel sauce. To do this, melt the butter in a saucepan over medium heat. Pour the flour with rain, constantly stirring, avoiding staining of the preparation.
When the flour becomes slightly dense, gradually pour in the milk. Cook by stirring constantly with a wooden spoon. When the sauce thickens, season to taste with salt, pepper and grated nutmeg.
Drain the water from the pasta before placing it in a baking dish. Then add the shrimp, pour over everything with bechamel sauce, then sprinkle with grated cheese.
Bake 30 minutes.
After this time, remove the shrimp and pasta gratin from the oven and serve immediately.