Baked macaroni with sausage ragù

If you lack time for fresh-pasta lasagne, macaroni, penne and similar pasta make a quick, tasty alternative. I made sausage sauce, but meat ragù, vegetable sauce or plain tomato sauce work well too.
INGREDIENTS FOR 8
800 G MACARONI
RAGÙ
6/7 SAUSAGES
1 CARROT
1 CELERY STALK
1 ONION
1 TIN PEELED TOMATOES
2 TABLESPOONS TOMATO PURÉE
EXTRA VIRGIN OLIVE OIL
SALT
PEPPER
BÉCHAMEL
80 G BUTTER
80 G ITALIAN 00 FLOUR
ABOUT 1 LITRE MILK
SALT
PEPPER
NUTMEG
GRATED GRANA PADANO
BUTTER
I wash and peel the vegetables.I finely chop the vegetables.I soften them in plenty of extra virgin olive oil in a saucepan.I remove the sausage casings and add the crumbled meat.I brown well, then add a tin of peeled tomatoes.I crush them and add tomato purée.I adjust salt and pepper, cover and simmer for 30 minutes.It should reduce without becoming too dry.Meanwhile, I cook the pasta until firm, at least 4 minutes before the time on the packet. I like Rummo because it is rough-textured and holds its shape. I cool the cooked pasta under running water and return it to the pot.I make classic béchamel: melt butter in a saucepan, add all the flour and stir the roux for a few minutes. Whisk in hot milk to avoid lumps, then add salt, pepper and nutmeg. Simmer for about ten minutes, keeping it fairly fluid.I mix the ragù and béchamel together. I pour the sauce over the pasta. I butter an aluminium tray, add the pasta and scatter generously with grated cheese and small knobs of butter.I bake at 180/200°C until golden with a delicious crust. Prepare ahead and bake before the meal; it takes 20 minutes.