If you are looking for a vegetarian dinner that feels genuinely satisfying and never like a compromise, this Mary Berry vegetable lasagne recipe is exactly what you need. Packed with earthy mushrooms, baby spinach, and a rich tomato sauce, then layered with a velvety Gruyère cheese béchamel, every forkful delivers real comfort. It is the kind of crowd-pleasing, make-ahead bake that earns a permanent spot in your weekly rotation. Whether you are cooking for the family on a weeknight or preparing ahead for a gathering, this classic dish comes through every single time.
Ingredients
For the Vegetable Filling
- 2 tbsp olive oil
- 1 large onion, finely chopped
- 2 garlic cloves, crushed
- 400g chestnut mushrooms, sliced
- 2 x 400g tins chopped tomatoes
- 2 tbsp sun-dried tomato paste
- 1 tbsp balsamic vinegar
- 2 tsp caster sugar
- 1 tbsp fresh thyme leaves
- 100g baby spinach
- Salt and freshly ground black pepper
For the White Sauce
- 75g butter
- 75g plain flour
- 900ml hot whole milk
- 2 tsp Dijon mustard
- 100g Gruyère cheese, grated (plus extra for topping)
- Salt and pepper to taste
To Assemble
- 6 to 8 dried lasagne sheets (no-boil variety recommended)
- 250g mozzarella, torn or sliced
How to Make Mary Berry Vegetable Lasagne
Follow these steps for a perfectly layered, golden vegetable lasagne every time.
- Preheat the oven to 200°C / 180°C Fan / Gas 6.
- Make the vegetable sauce. Heat the olive oil in a large, deep frying pan over medium heat. Add the onion and cook for 3 to 4 minutes until softened. Add the mushrooms and crushed garlic and fry for another 2 minutes, stirring regularly. Tip in the tinned tomatoes, sun-dried tomato paste, balsamic vinegar, sugar, and thyme. Stir to combine.
- Wilt the spinach. Add the baby spinach to the pan. Continue cooking for 5 minutes, stirring, until the spinach has completely wilted and the sauce is bubbling and slightly thickened. Season well with salt and pepper, then set aside.
- Make the cheese sauce. Melt the butter in a saucepan over medium heat. Stir in the flour and cook for 1 minute to form a smooth roux. Gradually whisk in the hot milk, a little at a time, ensuring no lumps form. Keep whisking as the sauce comes to a gentle boil and thickens. Stir in the Dijon mustard and half the Gruyère. Season to taste.
- Assemble the lasagne. Use a 1.8 litre (3 pint) ovenproof dish. Spoon one-third of the vegetable sauce over the base. Spread one-third of the cheese sauce over it. Lay half the lasagne sheets in a single layer on top.
- Repeat the layers. Add half the remaining vegetable sauce, followed by half the remaining cheese sauce. Scatter over half the mozzarella. Lay the remaining lasagne sheets on top. Spread the rest of the vegetable sauce, then the remaining cheese sauce over the top. Scatter the remaining mozzarella and sprinkle over the rest of the Gruyère.
- Bake. Place in the preheated oven and bake for 30 to 35 minutes, until the top is deep golden brown and the sauce is bubbling around the edges.
- Rest before serving. Remove from the oven and leave to rest for 10 minutes. This step is essential as it allows the layers to settle and makes slicing much cleaner.
Tips for the Best Vegetable Lasagne
Getting a vegetable lasagne right comes down to a few key details. Follow these tips and you will consistently produce a beautifully set, deeply flavoured bake.
- Use freshly grated Gruyère rather than pre-shredded cheese. It melts far more smoothly into the sauce.
- Always use hot milk when making the béchamel. It speeds up thickening and prevents lumps.
- Season both sauces generously. The pasta and vegetables absorb a lot of salt during baking, so do not hold back at the seasoning stage.
- Assemble the dish a few hours (or even a day) before baking. This allows the dried pasta sheets to absorb moisture from the sauces, resulting in a more tender and flavourful bake.
- Grate a pinch of fresh nutmeg into the white sauce for a subtly warm depth of flavour that brings the whole dish together.
How do I stop vegetable lasagne from being watery?
The most common cause is undercooking the vegetable sauce. Make sure the sauce is actively bubbling and has reduced slightly before you begin layering. Spinach and mushrooms both release significant moisture, so cook them until that liquid has evaporated. Never skip reducing the tomato base to a thicker consistency before assembly.
Can I make this ahead of time?
Yes, absolutely. Assemble the lasagne fully, cover tightly with cling film, and refrigerate for up to 24 hours before baking. Add an extra 5 to 10 minutes to the baking time if the dish goes straight from the fridge into the oven. The flavours actually improve as the layers settle overnight, making this one of the best make-ahead recipes in Mary Berry’s repertoire.
How do I get a really golden top?
Use a combination of Gruyère and mozzarella on the final layer. Gruyère browns beautifully, while mozzarella gives those irresistible golden-edged bubbles. Bake uncovered for the full time so the heat can work on the cheese. If after 35 minutes the top is still pale, switch the oven to the grill setting for the final 3 to 4 minutes, watching carefully to avoid burning.
Serving Suggestions
This vegetable lasagne is a complete, hearty main course on its own. To round out the meal, consider:
- A crisp green salad dressed with a light lemon vinaigrette to cut through the richness of the cheese sauce
- Crusty garlic bread or warm ciabatta for mopping up the extra sauce
- Roasted Mediterranean vegetables such as courgette or aubergine alongside
- A simple tomato and basil salad for a fresh, summery contrast
- A glass of chilled Pinot Grigio or Sauvignon Blanc for adults
Storage
Room Temperature
Do not leave baked lasagne at room temperature for more than 2 hours. Bacteria multiply quickly in warm, moist food, so cool it down promptly and transfer to the fridge or freezer.
Refrigerator
Once fully cooled, cover the dish tightly with foil or transfer portions to an airtight container. It will keep well in the refrigerator for up to 3 days. Reheat individual servings in the microwave on full power for 2 to 3 minutes, or cover the whole dish with foil and reheat in the oven at 180°C for 20 to 25 minutes until piping hot throughout.
Freezing
This lasagne freezes exceptionally well. For best results, freeze it unbaked. Assemble the dish, allow it to cool completely if needed, then wrap tightly in a double layer of cling film followed by foil. Freeze for up to 1 month. Thaw overnight in the refrigerator before baking as directed. For individual portions of baked lasagne, freeze in airtight containers for up to 2 months.
Nutrition (Per Serving)
Based on 6 servings. Values are approximate.
| Nutrient | Amount |
| Calories | 480 kcal |
| Protein | 22g |
| Carbohydrates | 38g |
| Fat | 26g |
| Saturated Fat | 14g |
| Fibre | 4g |
| Sugar | 10g |
| Salt | 1.1g |
FAQ’s
Can I use cheddar instead of Gruyère?
Yes. A strong, mature cheddar works well and has a bolder, slightly sharper flavour. The sauce will still be creamy and rich.
Do I need to pre-cook the lasagne sheets?
No. This recipe is designed for no-boil or oven-ready dried sheets. The moisture from the sauces softens the pasta perfectly during baking, especially if you assemble the dish ahead of time.
Can I add other vegetables to the filling?
Absolutely. Diced courgette, roasted red peppers, aubergine, or cubed butternut squash all work beautifully. Just make sure any extra vegetables are cooked until tender and most of their moisture has evaporated before layering.
Is this recipe suitable for freezing before baking?
Yes. Assemble the lasagne, wrap it tightly, and freeze unbaked for up to 1 month. Thaw overnight in the fridge before baking as directed.
Can I make a vegan version?
Yes. Use plant-based milk such as oat or almond for the béchamel, swap the butter for a vegan alternative, and replace the cheese with vegan mozzarella and nutritional yeast for a similar savoury depth.
How long should I let it rest after baking?
At least 10 minutes. Resting gives the layers time to firm up, which makes slicing much cleaner and neater.
Final Thoughts
Mary Berry’s vegetable lasagne is the kind of recipe that proves meat-free cooking can be every bit as hearty and comforting as any classic. The combination of a deeply savoury mushroom and spinach tomato sauce with a nutty Gruyère béchamel is genuinely hard to beat. It layers up beautifully, holds together well when sliced, and tastes even better the next day.
Whether you are feeding a vegetarian household, batch cooking for the week, or simply craving proper comfort food, this foolproof recipe delivers on every level. Follow the tips for avoiding a watery filling, give the layers enough time to rest after baking, and you will have a golden, bubbling lasagne that brings everyone back for seconds.
