Big Roasted Vegetable Lasagne


Preparation info

  • Serves


    • Difficulty


Appears in

The Vegetarian Kitchen

The Vegetarian Kitchen

By Prue Leith and Peta Leith

Published 2019

  • About

This is a recipe I always turn to when I have a crowd to feed. It’s hugely popular with everyone, kids adore it, and the beauty of it is that it can all be made in advance before anyone arrives, so you’re free to enjoy yourself once they’re there. All you need to do is remember to turn the oven on!


  • 1 aubergine, diced
  • 2 red onions, roughly diced
  • 3 red peppers, deseeded and roughly diced
  • 280 g baby plum or cherry tomatoes, chopped
  • 2 tbsp vegetable oil plus extra for coating
  • salt and black pepper
  • 1 garlic bulb
  • 1 large courgette, cut into bite-sized pieces
  • 1 tbsp tomato purée
  • a good bunch of basil, leaves roughly torn, plus extra to top
  • 450 ml cold whole milk
  • 20 g unsalted butter
  • 20 g plain flour
  • a pinch of English mustard powder
  • 100 g mature Cheddar cheese, grated
  • 60 g vegetarian Parmesan-style cheese, grated
  • 200 g dried lasagne sheets


    1. Heat the oven to 200°C/fan 180°C/gas mark 6.
    2. In a large roasting tray, toss the aubergine, red onions, red peppers and tomatoes with the 2 tablespoons of vegetable oil, and season with salt and black pepper. Cut the top off the garlic bulb in order to expose each clove at the top, then wrap it in foil and add it to the roasting tray.
    3. Roast the vegetables in the oven for 35 minutes, then add the courgette and stir through the tomato purée. Return to the oven for 25 minutes, then remove from the oven and stir in the torn basil leaves.
    4. When cool enough to handle, remove the garlic from the foil and squeeze the now-soft garlic flesh out of it, then stir it into the other vegetables.
    5. While the vegetables are roasting, make the cheese sauce. Combine the milk, butter, flour and mustard powder in a saucepan, set it over a medium heat and whisk frequently until the butter has melted and the flour is all incorporated. Bring the mixture to the boil and cook, whisking regularly, until the sauce has thickened enough to coat the back of a spoon.
    6. Remove the sauce from the heat, then whisk in the grated Cheddar and half the grated vegetarian Parmesan-style cheese. Taste, then season with salt and black pepper.
    7. Bring a large pan of salted water to the boil, then cook the lasagne sheets in it for 8–10 minutes, until just al dente. Use tongs to remove them, then coat them in vegetable oil to prevent them from sticking to one another.
    8. Assemble the lasagne in a large, rectangular ovenproof dish (about 30 × 20 cm/12 × 8 in and 10 cm/4 in deep). Put a layer of roasted vegetables in the base, top it with a layer of lasagne sheets, then a layer of cheese sauce, and repeat until you have used everything up. You should end with the cheese sauce on the top. Scatter the remaining Parmesan-style cheese over the top and return to the oven for 35–40 minutes, until browned and piping hot. Top with extra basil if desired.