First, we have to roast the veggies. So, preheat the oven to 400 F. Season the veggies with olive oil thoroughly, salt, and pepper. Place on baking pans flat and bake for 20 minutes until tender. Flip half way through. Season generously.
While that is roasting, make the tomato sauce. Add the olive oil to a pan with the onions and garlic then saute until fragrant.
To that, add the tomato pure, tomato paste, and the spicy tomato pesto for some heat along with the salt, pepper, and dried oregano. Stir together and allow to cook together for a few minutes. Taste and adjust salt level if needed. Set aside.
For the bechamel, in a pot add the butter and melt it then add the flour and stir until a roux is formed and slightly thickens and caramelizes.
To this, add the cream and milk in one cup at a time stirring consistently on medium high heat. Add salt, pepper, and add nutmeg to this and stir. Keep stirring until the bechamel starts to slightly thicken then add the parmesan cheese and keep stirring until thick and creamy but pourable. Set aside.