Traditional lasagna: absolutely not. Bolognese, besciamella, cheese. That's it.

But of course, so what? If you like spinach in it, but spinach in it. If you ike other veggies in it, put other veggies in it.

Best lasgna I ever made I included horse meat and finely chopped serrano ham. Not traditional, but so what? Everyone at the table loved it, and the women looked at me longingly (okay, it was my girlfriend).