Mary Berry Onion And Mushroom Tart

This classic British savoury bake serves six and brings comfort to the table with balanced flavours and an elegant finish.

The method uses a 23 cm loose-bottom tin to ensure the pastry base sets perfectly. Prep takes about 25 minutes, with a 35-minute cook time, so it fits a relaxed afternoon of baking.

This dish offers roughly 380 kcal per portion, making it a sensible choice for lunch, light dinners or when you are entertaining guests. The filling pairs earthy fungi and soft, caramelised onions to give a rich yet balanced taste.

Practical tips: the recipe is designed for home cooks and asks for common kit such as a whisk. Follow the steps to make a crisp base that holds a creamy filling without going soggy.

Key Takeaways

• Serves six and uses a 23 cm loose-bottom tin for best results.
• Preparation is 25 minutes; cooking is 35 minutes — ideal for sensible meal planning.
• Each portion is about 380 kcal, a balanced savoury option.
• Simple techniques produce a crisp pastry and golden finish.
• The approachable recipe suits home bakers and small gatherings.

The Appeal of a Mary Berry Onion And Mushroom Tart

This savoury bake captures the quiet pleasures of British home cooking. It sits firmly in the Simple Comforts collection, where reliable technique meets approachable flavour.

The charm comes from balance. Earthy mushrooms add depth without heaviness. Sweet, gently softened onions bring a bright contrast to the creamy savoury custard.

Why it comforts: the flavours are familiar and well measured. The result is elegant yet homey. It slices neatly and travels well for picnics or a relaxed supper.

The recipe trusts quality ingredients and simple steps. That focus delivers consistent results, whether you’re cooking for family or guests. Small touches — careful sweating of the onion and a short sauté of the fungi — make all the difference.

• Consistent, elegant outcomes for everyday cooking.
• Depth from mushrooms, sweetness from onions for balanced flavour.
• Versatile enough for lunch, light dinner or picnic.

Essential Ingredients for Your Savoury Bake

A clear ingredient list sets you up for success before the oven even heats up.

Below are the essentials split between the pastry and the filling. Keep items chilled where noted to get the best results.

Pastry Essentials

For a classic shortcrust pastry you will need 200 g plain flour and 100 g cold unsalted butter. Add 2–3 tablespoons of cold water to bring the dough together.

Tip: Keep the butter and water cold to prevent shrinkage and to ensure a light, crisp pastry.

Filling Components

Whisk 3 large eggs with 200 ml double cream in a large mixing bowl until smooth. Season with salt and freshly ground black pepper to taste.

• 250 g sliced mushrooms for earthy depth.
• Fresh onions for sweetness and texture.
• 100 g mature cheddar cheese to add sharpness.

Some Simple Comforts variations use puff pastry for a flakier base. Use high-quality ingredients and follow the measures for a reliable, home-friendly recipe.

Preparing the Perfect Pastry Base

Perfect pastry relies on a few simple habits that protect texture and flavour. Start by rubbing 100 g of cold butter into 200 g of flour until the mix looks like fine breadcrumbs. This method creates a base that bakes crisp and light.

Chill the dough for 20–30 minutes before rolling to prevent shrinkage while baking. Prick the centre of the pastry with a fork; this lets steam escape and stops the case puffing up unevenly.

Blind Baking Tips

Blind bake at 190°C (170°C fan) for 15 minutes with baking beans to set the base. Remove the beans and bake a further 5 minutes until the pastry is lightly golden.

If you use puff pastry, cut a 2 cm border and brush the edge with beaten egg. This seals the rim and creates a professional raised edge. For an even crisper bottom, place the tart tin on a hot baking tray before it goes into the oven.

Cooking the Onion and Mushroom Filling

Start on the hob: sweat the onions first, then brown the mushrooms to build depth of flavour. Use a large pan so the vegetables colour rather than steam.

Heat 2 tbsp olive oil in the pan and fry 4 large onions over high heat for 3–4 minutes. Reduce the heat briefly, then stir in 1 tsp light brown sugar and 1 tsp balsamic vinegar. This lifts the natural sweetness.

Turn the heat back up and add the sliced mushrooms. Fry on high for 2–3 minutes, then cover for 3–4 minutes to steam and release moisture. Uncover and fry on high until all liquid has evaporated.

• Tip: melt 25 g unsalted butter first to soften the onion gently if you prefer a richer base.
• Cook until the mixture is dry so the custard stays set and not watery.
• Season well with salt and freshly ground black pepper before assembly.

Allow the filling to cool slightly before you add it to the pastry case. Mary Berry notes that thorough cooking makes for a confident, well-set finish.

Assembling the Tart Components

Place the blind‑baked pastry base on a flat tray and keep the raised rim ready. Spread the cooled onions mushrooms mixture evenly so the vegetables sit well inside the border.

In a mixing bowl, whisk 3 large eggs with 200 ml double cream until the custard is completely smooth. Season with salt and freshly ground black pepper for even seasoning throughout the mixture.

Sprinkle 100 g mature cheddar cheese over the vegetables to help bind the filling and add a savoury lift. If you use puff pastry, follow the same assembly; distribute the vegetables evenly for balanced slices.

Brush the pastry rim with beaten egg for colour. Pour the egg and cream mix slowly so it reaches the edges without spilling over. Using a pan to fry high heat before assembly ensures there is no excess liquid and keeps the base crisp.

Quick checklist

• Spread filling across the pastry base.
• Add cheddar, then pour the custard from a bowl.
• Brush rim with egg and avoid overfilling.

Baking Techniques for a Golden Finish

Getting the final bake right depends on steady oven temperature and careful timing. A consistent heat gives the pastry a crisp rim while the custard sets evenly. Small checks during the last stage prevent overcooking and keep the centre soft and creamy.

Oven temperature

Preheat to 190°C (170°C fan). This setting promotes a golden base and an even bake across the case. Keep the oven stable for the full 30–35 minutes of the final baking stage.

Achieving the wobble

Bake until the custard shows a slight wobble in the centre. Remove when it still moves gently — residual heat will finish the mixture without drying it out. This ensures a light, creamy texture rather than a dry set.

Resting time

Rest the bake for 10–15 minutes on a cooling rack. This pause firms the filling and makes slicing clean and simple. If edges brown too quickly, tent them loosely with foil while the centre finishes.

Key reminders

• Place the tin on a baking tray so the base receives direct heat for a crisp finish.
• Avoid exceeding 35 minutes at the recommended temperature to protect the egg and cream mixture.
• Use foil to shield edges if they brown before the centre is set.

Customising Your Savoury Tart

Simple swaps in the filling let you adapt this savoury pastry for any meal.

Choose your fungi: use button mushrooms or chestnut varieties to alter texture and flavour. Both work well when sliced and fried in 2 tablespoons of olive oil over high heat so they brown, not steam.

Add herbs and sweetness for depth. Try 1 teaspoon of chopped sage or thyme and a tsp light brown sugar with a splash of balsamic to lift the onions during frying.

For a lighter take, replace some cream with milk and choose a reduced-fat cheddar. Or swap cheddar for Gruyère to give a nuttier, richer finish.

Want a Mediterranean twist? Fold in 175 g of drained, cut large pieces of chargrilled artichokes. You can also add spinach or other seasonal vegetables to boost nutrition.

“Small, thoughtful swaps in ingredients keep the technique unchanged while changing the character of the recipe.”

• Tip: Always let cooked vegetables cool before adding to the pastry so the custard sets cleanly.
• Experiment with cheese and herbs, keeping the pan hot to get good colour on the vegetables.

Serving Suggestions for a Complete Meal

Complement the rich filling with bright, crisp accompaniments for contrast and texture. Small sides lift the plate and make the bake feel like a thoughtful meal rather than a single dish.

Pairing with Fresh Salads

Green salads work particularly well. Serve your tart hot with a fresh leaf salad to add crunch and a cleansing note against the creamy filling.

• Fresh salad: a simple mixed leaf salad with a light vinaigrette and 1 tsp chopped thyme or parsley complements the onions and mushrooms.
• Roasted cherry tomatoes or steamed greens keep the meal light and bring out the savoury cheese and egg flavours.
• For a heartier option, add new potatoes; this turns the bake into a filling evening meal.
• The tart also serves cold for picnics; pair with a tangy chutney and drained cut large pieces of roasted veg for variety.
• Using button mushrooms gives a neat, uniform texture that slices well for guests.
• Allow the bake to rest for at least 10 minutes so the egg-based custard firms and slices cleanly.

Storing and Reheating Your Leftovers

Leftovers can taste nearly as good as the fresh slice if you store and reheat them correctly. After baking, allow the tart to cool fully on a rack before covering.

Refrigerate wrapped or in an airtight container for up to 2 days. Cooling first stops condensation that would soften the pastry base.

For best results, warm slices in a low oven rather than a microwave. A gentle oven restores the crisp pastry and keeps the custard set.

If you used puff pastry, the low oven is important to revive flakiness. Reheat at a moderate temperature for 10–15 minutes so the heat penetrates without drying the filling.

• Avoid microwaves; they make the pastry soggy and ruin texture.
• Mary Berry suggests serving at room temperature if eating the same day.
• For longer storage, freeze tightly wrapped slices; note the custard texture may change slightly after thawing.

Conclusion

A well-made savoury case is proof that simple technique yields dependable results every time. This Mary Berry recipe shows how basic storecupboard items can deliver true comfort without fuss.

Follow the steps for blind baking, cool the filling slightly and use a steady oven temperature to get a crisp base and a creamy centre. Small habits in timing and heat make the difference.

Final thought: from prep to slice, this classic from the Simple Comforts collection rewards care with balanced flavour and reliable results. Enjoy it with family and friends.