Slice courgettes into rounds and the peppers into strips.
Heat a griddle pan and griddle vegetables until chard and cooked through (about 10 minutes) or put on baking tray, drizzle in olive oil, season and roast the vegetables at 180°C / 160°C fan for 15 minutes.
To make the white sauce whisk the oil and flour in pan on a low heat. Once combined cook for 5 minutes then slowly whisk in the nut milk a little at a time. Whisk on a low heat until thick. Take off the heat, add nutmeg, Dijon mustard, nutritional yeast flakes and season to taste.
Layer the lasagne starting with Bay’s Kitchen Tomato & Basil Stir-in Sauce then add a few slices of courgette, peppers, basil leaves and spinach. Then add a layer of lasagne sheets followed by the white sauce. Repeat until your baking dish is full making sure you finish with a layer of white sauce. Cover the top with the grated cheese (if using) before putting in the oven.
Bake in the oven at 180°C / 160°C fan for 30-40 minutes until golden on top.