Preheat the oven to 200C. Mince the garlic and chop all your vegetables into chunky pieces.
Add the vegetables, thyme, oregano, olive oil, balsamic vinegar and salt to the lasagna dish. Mix well, cover with foil and cook in the oven for 45 minutes.
While the vegetables are roasting, prepare the pesto. Add the olive oil, garlic, basil and pine nuts to a blender and process until smooth.
For the béchamel, melt the butter in a pot over medium heat. Add the flour, stirring constantly for two minutes until a paste is formed. Gradually add the milk, no more than ½ a cup at a time, stirring constantly until the mixture thickens. Once all the milk is incorporated, add the nutmeg, a pinch of salt and cheese. Stir through until the cheese has melted.
Transfer the roasted vegetables to a large mixing bowl and stir in the passata.
To build the lasagna start with a layer of vegetable sauce, a layer of pasta, a layer of vegetable sauce, pesto, and béchamel. Smooth using a spatula and repeat to the top of the dish. Make the last layers of the pasta and béchamel. Cook in the oven covered according to your pasta packet instructions. Cook uncovered for the last 10 minutes.
Allow 10 minutes to cool down before slicing through.