Vegetable lasagne

A hearty pasta bake filled with a rich vegetable sauce and creamy bechamel.

Allergens: none of the 14 main allergens in the usual versions of these ingredients. Brands differ, so always check the labels on what you buy.

Not every ingredient has a checked price at Aldi, Lidl, Asda, Morrisons, Iceland, so they aren't compared here.

Ingredients and prices

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Prices checked on 4 October 2026 from each supermarket's own listing or a price-comparison site. Each shop's unit price (or pack size) is shown under its price, and "cost of what this recipe uses" compares like with like (tap a price to see its source). Cheapest in each row is ticked. Prices, offers and pack sizes change; loyalty-card prices are not included unless stated.

Method

The method is written for 6. For a different number, use the amounts in the table above.

1. Prep the vegetables. Peel and finely dice 1 onion (about 12 small cubes, 5mm each). Peel and grate 2 carrots (use a box grater or food processor for fine, even shreds). Trim the ends off 2 courgettes, halve lengthways, then slice into 3mm-thick half-moons. Finely slice 2 spring onions (white and pale green parts only).
2. Make the béchamel sauce. Melt 50g unsalted butter in a medium saucepan (24cm diameter) over medium heat for 2 minutes, until foaming. Stir in 50g plain flour and cook for 1-2 minutes, stirring constantly, until it smells nutty and turns golden (this is the roux). Slowly whisk in 500ml semi-skimmed milk, 50ml at a time, ensuring no lumps form. Return to medium heat and simmer for 5-7 minutes, stirring often, until thickened enough to coat the back of a spoon. Season with ½ tsp salt and ¼ tsp black pepper. Taste and adjust seasoning if needed (add more salt or pepper). Remove from heat and stir in 200g grated cheddar until melted and smooth. Cover and keep warm.
3. Cook the pasta. Bring a large saucepan of salted water (1.5 litres, enough to cover) to the boil over high heat. Add 250g dried lasagne sheets and cook for 10-12 minutes, stirring occasionally, until al dente (slightly firm to bite). Drain in a colander, rinse under cold water for 10 seconds to stop cooking, and set aside. Preheat the oven to 180°C (fan 160°C, gas mark 4).
4. Cook the vegetables. Heat 1 tbsp vegetable oil in a large frying pan (24cm diameter) over medium heat for 1 minute. Add the diced onion and cook for 3-4 minutes, stirring often, until soft and translucent. Add the grated carrots, sliced courgettes, and frozen mixed vegetables, stirring to combine. Cook for 5-6 minutes, until the courgettes soften slightly and the carrots begin to colour. Stir in the 2 tins chopped tomatoes (400g total), 1 tsp salt, and ½ tsp black pepper. Simmer uncovered for 8-10 minutes, stirring occasionally, until thickened and the liquid reduces by half. Taste and adjust seasoning. Remove from heat and stir in the sliced spring onions.
5. Assemble the lasagne. Lightly grease a 20x30cm lasagne dish with a little oil. Spread ⅓ of the tomato mixture over the base. Top with ⅓ of the lasagne sheets, slightly overlapping if needed. Spread ⅓ of the béchamel sauce over the pasta, then sprinkle with ⅓ of the remaining grated cheddar (about 65g). Repeat the layers, ending with the final layer of pasta, remaining béchamel, and the rest of the cheese. Cover tightly with cling film and refrigerate for 30 minutes (this prevents the top from drying out).
6. Bake the lasagne. Remove the cling film and cover the dish loosely with aluminium foil (this prevents the top from browning too quickly). Bake in the preheated oven for 30 minutes. Remove the foil and bake for a further 15-20 minutes, until the top is golden and bubbling. If the edges brown too quickly, cover them with foil for the last 5 minutes. Let it rest for 10 minutes before serving (this helps it set).
7. Serve and store. Slice into 6 equal portions using a large, sharp knife. Serve immediately with extra grated cheddar on the side if desired. To store, cool the lasagne to room temperature (no more than 2 hours), then cover and refrigerate for up to 48 hours (2 days). To reheat, cover with foil and bake at 160°C (fan 140°C) for 25-30 minutes, until steaming hot throughout. Do not reheat more than once. For freezing, portion into airtight containers, label with the date, and freeze for up to 3 months. Defrost in the fridge overnight and reheat as above.
8. Batch-cook and prep ahead. Assemble the lasagne up to the final cheese layer, cover, and refrigerate for up to 24 hours. Bake as instructed when ready to serve. Alternatively, cook the béchamel and tomato sauce separately, then reheat gently before assembling. Pre-chopped vegetables can be stored in airtight containers in the fridge for 2 days or frozen for 1 month (blanch courgettes for 2 minutes in boiling water before freezing).

Tips

• {'tip': 'Swap courgettes for **aubergine (1 large, diced)** or **mushrooms (300g, sliced)** for a richer flavour. Use **reduced-fat cheese (150g)** or **feta (100g, crumbled)** to cut costs or calories. For a meaty texture, stir in **100g cooked lentils or 150g minced lentils** with the tomatoes.'}
• {'tip': 'Double the recipe and freeze half immediately. Portion into **4 individual lasagne dishes (15x20cm)** for easy single servings. Label with the date and reheat as above, ensuring it’s steaming hot throughout before eating.'}
• {'tip': 'To reheat safely, cover the lasagne with foil to retain moisture. If using a microwave, cover with a damp paper towel and heat in **1-minute intervals**, stirring between each, until hot. **Never reheat from frozen**—always defrost in the fridge first.'}

Nothing wasted: your leftover ingredients

Supermarkets sell set pack sizes, so you'll have some ingredients left. Here's how to keep them, and other recipes here that use them up.

• Dried pasta · about 250g left
  Dry stores keep for months sealed in the cupboard, so nothing goes to waste. Use it in: Creamy Tomato & Hidden Veg Pasta Bake, Tuna and Sweetcorn Pasta Bake.
• Onion · about 700g left
  Chop the rest and freeze it flat in a bag: it cooks straight from frozen in soups, curries and sauces. Whole onions keep for weeks somewhere cool, dark and dry. Use it in: Chilli con carne, Egg fried rice, Creamy Tomato & Hidden Veg Pasta Bake.
• Carrots · about 340g left
  Keep in the fridge salad drawer for up to 2-3 weeks, or slice and freeze. Great grated into bolognese, chilli or soup. Use it in: Lentil and vegetable soup, Creamy Tomato & Hidden Veg Pasta Bake, One-pan chicken, potatoes and veg.
• Frozen mixed vegetables · about 700g left
  Keep the rest frozen: just reseal the bag. Use it in: Lentil and vegetable soup, Creamy Tomato & Hidden Veg Pasta Bake, Slow Cooker Lentil Chilli.
• Cheddar cheese · about 200g left
  Keep wrapped in the fridge. Grate any extra and freeze it: it melts straight from frozen on pasta bakes and toasties. Use it in: Creamy Tomato & Hidden Veg Pasta Bake, Tuna and Sweetcorn Pasta Bake, Cheesy Bean & Rice Casserole.
• Milk (semi-skimmed) · about 500ml left
  Keep in the fridge and use by the date on the pack; milk can also be frozen. Use it in: Rich Chocolate Mousse, Beef and Ale Pie, Banana muffins.
• Plain flour · about 1.45kg left
  Dry stores keep for months sealed in the cupboard, so nothing goes to waste. Use it in: Banana muffins, Ginger Cake, Turkey Burgers with Sweet Potato Fries.
• Unsalted butter · about 200g left
  Check the label: most raw ingredients can be frozen before their use-by date, and cupboard staples keep for months. Use it in: Banana muffins, Ginger Cake, Pad Thai with Chicken.

Storing leftovers

Cool leftovers and put them in the fridge or freezer within 1–2 hours. Eat fridge leftovers within 2 days, or freeze them. Defrost in the fridge and reheat only once, until steaming hot all the way through (Food Standards Agency guidance).