I was inspired to make this last night. The balsamella was an absolutely beautiful suggestion! My version used barilla "home style" no-boil noodles. These are flat instead of ruffled, and are pretty thin. I don't have a pasta machine. For the balsamella, I added maybe 1/3 C parm-reg to 2 C of thickish balsamella (3 T butter, 3 T flour, 2 C milk, then an extra T of butter to finish (and heavy on the nutmeg :) but I didn't measure anything, I just microplaned some in until it looked good. For the ragu I used half spicy sausage and half ground beef. Mixed 2 cups of mozz with the ricotta and a couple of eggs and some pepper. I colored it up under the broiler after it was bubbling, and it turned out just gorgeous. I took a picture, but it's still on the camera so I can't post it. Taste notes: add salt to the ragu next time, and next time use all sausage or add some red pepper flakes; the spicy sausage didn't cut through very well. Add more marinara becuase the noodles soaked up a lot of moisture.
