I'm making a lasagne with a creamy courgette and rocket filling. I like a crispy, cheesy top to a lasagne so I'll use béchamel with Parmesan on the top. I want to add a simple garlicky tomato sauce somewhere but I'm not sure where best to add it. A layer on it's own? Or do I run the risk of it mixing with the courgette mixture and go pasta, tomato, courgette stuff and repeat as necessary?
All thoughts welcome! TIA