In a saucepan with lightly salted water, boil carrots and broccoli for 5 minutes until firm to the bite. Drain and set aside.
Meanwhile heat a frying pan with oil; gently stir onions until they soften. Add garlic and courgettes and fry for 5 minutes, stirring frequently.
Take the pan off the heat and stir in corn, carrots, broccoli, tofu, cayenne, oregano, basil and rosemary.
Spread a layer of passata in a baking dish; top with a layer of lasagne sheets. Add another layer of passata and spoon the vegetable mixture on top. Add a layer of lasagne sheets, top with more passata and spread sweet potato mash on top of that. Add a last layer of lasagne sheets and top with passata. Arrange the sliced tomatoes on top. Sprinkle ground cashews over the top of the lasagne and cover with foil.
Bake in preheated oven for 45 minutes. Uncover and bake for another 15 minutes until golden brown on top.