This is absolutely a favourite! The grilled veg used are totally interchangeable with whatever your preferences and the time of the year. It’s the roasted garlic and sun-dried tomatoes that make the tomato sauce stand out from the crowd.
1. Preheat the oven to 200°C/gas mark 6.
2. Cut all the vegetables into bite-sized pieces, then place in a large mixing bowl with the oil, vinegar and salt. Spread out on 1 or 2 baking trays and roast in the oven for 25 to 30 minutes.
3. To make the tomato sauce, cut the top off the garlic bulb. Wrap it in tin foil and roast with the veg for 30 minutes.
4. Heat the oil in a large pan over a low heat. Add the onion and cook for 10 minutes, covered, stirring occasionally, until softened. Stir in the remaining ingredients for the tomato sauce. Bring to the boil, then reduce to a simmer. Remove the bay leaves from the sauce. Squeeze the roasted garlic cloves into the sauce, then blend the sauce until smooth. Stir the roasted veg into the blended sauce.
5. To make the béchamel, put the milk into a medium pan set over a medium heat, stirring occasionally. In another pan, melt the butter or heat the oil gently over a low heat. Whisk the flour into the fat for about 5 minutes to form a roux.
6. When the milk comes to the boil, take it off the heat and add it to the roux a little at a time, whisking continuously. Continue to stir for 5 to 10 minutes over a low heat, until the sauce thickens. Remove from the heat and stir in the cheese. Season with the nutmeg, salt and pepper.
7. To assemble, spread one-fifth of the béchamel in the bottom of a large baking dish, then cover with a layer of lasagne sheets. Add half the tomato and veg sauce, spreading it out evenly over the lasagne sheets. Cover with another layer of lasagne sheets, then spread over half the béchamel. Add 50g of the Cheddar over the béchamel, then spread over the remaining tomato and veg sauce. Add a final layer of lasagne, followed by the remaining béchamel.
8. Scatter the rest of the Cheddar on top and bake in the oven for about 30 minutes, until bubbling and golden. Allow to stand for 5 minutes before cutting into slices.