Ekani Ella Mary Berry’s Onion and Mushroom Tart is a beautifully simple British bake that highlights earthy mushrooms, gently softened onions, and a creamy savoury custard set in crisp shortcrust pastry. The flavour is rich yet balanced, with natural sweetness from the onions and depth from the mushrooms. Ideal for lunch, light dinners, picnics, or entertaining, this tart uses classic baking techniques and comes together in about an hour, delivering dependable, elegant results.
What is Mary Berry’s onion and Mushroom Tart?
This tart is a traditional savoury bake made with a buttery pastry base, a soft-set egg and cream filling, and a generous layer of cooked onions and mushrooms. Unlike heavier versions, it focuses on clean flavours and a smooth texture, making it easy to slice and serve warm or cold.
Other Popular Mary Berry Recipes
Why This Recipe Is Worth Trying
- Classic British flavours – Familiar, comforting, and well-balanced
- Earthy depth – Mushrooms add richness without heaviness
- Crisp pastry base – Proper blind baking keeps it light
- Versatile serving – Works for lunch, brunch, or supper
- Make-ahead friendly – Tastes great the next day
Essential Ingredients to Make Mary Berry’s Onion and Mushroom Tart
For the Shortcrust Pastry
- Plain flour: 200 g
- Cold unsalted butter: 100 g, diced
- Cold water: 2–3 tablespoons
For the Filling
- Onions: 2 medium, thinly sliced
- Mushrooms: 250 g, sliced
- Unsalted butter: 25 g
- Eggs: 3 large
- Double cream: 200 ml
- Milk: 100 ml
- Mature cheddar cheese: 100 g, grated
- Salt: to taste
- Black pepper: to taste
Handy Kitchen Tools for Best Results
- 23 cm loose-bottom tart tin
- Rolling pin
- Baking beans or rice
- Frying pan
- Mixing bowl and whisk
- Sharp knife
Step-by-Step Guide to Making Mary Berry’s Onion and Mushroom Tart
- Prepare the pastry – Rub the butter into the flour until breadcrumb-like. Add cold water gradually and bring together into a soft dough.
- Chill the dough – Wrap and refrigerate for 20–30 minutes to prevent shrinkage.
- Line the tart tin – Roll out the pastry, line the tin, trim edges, and prick the base lightly.
- Blind bake – Bake at 190°C (170°C fan) for 15 minutes with baking beans, then 5 minutes uncovered until lightly golden.
- Cook the vegetables – Melt butter in a pan, add onions, and cook gently until soft. Add mushrooms and cook until the moisture evaporates.
- Make the custard – Whisk eggs, cream, milk, salt, and black pepper until smooth.
- Assemble the tart – Spread the onion and mushroom mixture over the pastry, sprinkle with cheese, and pour over the custard.
- Bake gently – Bake for 30–35 minutes until just set with a slight wobble in the centre.
- Rest before slicing – Allow to stand for 10–15 minutes for clean slices.
What I Got Wrong (And How I Fixed It)
- Soggy base – Fully blind baking solved the issue
- Watery filling – Cooking mushrooms until dry improved the texture
- Overcooked custard – Lower heat kept it creamy
- Uneven flavour – Proper seasoning made a big difference
Healthier Version of Mary Berry’s Onion and Mushroom Tart
To lighten this tart, use semi-skimmed milk instead of some of the cream and reduce the cheese slightly. Adding extra mushrooms increases volume without adding richness.
Ingredient Substitutions for Mary Berry’s Onion and Mushroom Tart
- Ready-made shortcrust pastry for convenience
- Chestnut or button mushrooms instead of mixed varieties
- Gruyère instead of cheddar for a deeper flavour
- Single cream mixed with milk for a lighter custard
Pairing Ideas: What to Serve With Mary Berry’s Onion and Mushroom Tart
- Green leaf salad – Adds freshness and crunch
- Tomato chutney – Brings gentle sweetness
- Steamed greens – Keeps the plate light
- Roasted cherry tomatoes – Enhance savoury notes
- New potatoes – Turn it into a fuller meal
Expert Tips to Make a Perfect Mary Berry Onion and Mushroom Tart
- Cook vegetables thoroughly – Removes excess moisture
- Keep pastry cold – Ensures crispness
- Season in layers – Builds better flavour
- Bake on a lower shelf – Helps the base cook evenly
- Watch the centre – Remove while slightly wobbly
- Rest before cutting – Improves structure
Creative Ways to Customize Mary Berry’s Onion and Mushroom Tart
- Herb addition – Add thyme or parsley
- Caramelised onions – Boost sweetness
- Mustard layer – Spread lightly on the base
- Spinach mix-in – Add colour and nutrients
- Mini tarts – Perfect for parties
Storing Mary Berry’s Onion and Mushroom Tart the Right Way
- Room temperature – Serve the same day once cooled
- Refrigerated storage – Keep covered for up to 2 days
- Freezing option – Freeze baked slices tightly wrapped
- Reheat gently – Maintains texture
How to Reheat Mary Berry’s Onion and Mushroom Tart
Reheat in a low oven until warmed through. Avoid microwaving to keep the pastry crisp.
Nutritional Breakdown (Per Serving)
- Calories: ~380 kcal
- Carbohydrates: ~28 g
- Fats: ~25 g
- Protein: ~12 g
- Sugar: ~4 g
Mary Berry Onion and Mushroom Tart
This tart is a traditional savoury bake made with a buttery pastry base, a soft-set egg and cream filling, and a generous layer of cooked onions and mushrooms. Unlike heavier versions, it focuses on clean flavours and a smooth texture, making it easy to slice and serve warm or cold.
- Prep Time: 25
- Cook Time: 35
- Total Time: 1 hour
- Yield: 6
- Category: Savoury tart
- Method: Baking
- Cuisine: British
Ingredients
For the Shortcrust Pastry
-
Plain flour: 200 g
-
Cold unsalted butter: 100 g, diced
-
Cold water: 2–3 tablespoons
For the Filling
-
Onions: 2 medium, thinly sliced
-
Mushrooms: 250 g, sliced
-
Unsalted butter: 25 g
-
Eggs: 3 large
-
Double cream: 200 ml
-
Milk: 100 ml
-
Mature cheddar cheese: 100 g, grated
-
Salt: to taste
-
Black pepper: to taste
Instructions
-
Prepare the pastry – Rub the butter into the flour until breadcrumb-like. Add cold water gradually and bring together into a soft dough.
-
Chill the dough – Wrap and refrigerate for 20–30 minutes to prevent shrinkage.
-
Line the tart tin – Roll out the pastry, line the tin, trim edges, and prick the base lightly.
-
Blind bake – Bake at 190°C (170°C fan) for 15 minutes with baking beans, then 5 minutes uncovered until lightly golden.
-
Cook the vegetables – Melt butter in a pan, add onions, and cook gently until soft. Add mushrooms and cook until moisture evaporates.
-
Make the custard – Whisk eggs, cream, milk, salt, and black pepper until smooth.
-
Assemble the tart – Spread the onion and mushroom mixture over the pastry, sprinkle with cheese, and pour over the custard.
-
Bake gently – Bake for 30–35 minutes until just set with a slight wobble in the centre.
-
Rest before slicing – Allow to stand for 10–15 minutes for clean slices.
FAQs
Why does my onion and mushroom tart turn watery after baking?
This usually happens when the mushrooms release moisture during baking. Cooking the mushrooms until all excess liquid evaporates before assembling the tart helps keep the filling rich and well set.
Should onions and mushrooms be cooled before adding them to the tart?
Yes, allowing the cooked onions and mushrooms to cool slightly prevents steam from entering the custard. This helps the tart set evenly and avoids excess moisture.
How do I stop the pastry base from becoming soggy?
Blind baking the pastry until lightly golden is essential. Placing the tart tin on a hot baking tray also helps the base cook evenly and stay crisp.
Can Mary Berry onion and mushroom tart be served cold?
Yes, this tart tastes excellent cold. Let it cool completely so the filling firms up, making it easy to slice cleanly for picnics or lunches.
Wrapping It Up
Mary Berry’s Onion and Mushroom Tart is a dependable savoury bake that proves simple ingredients can deliver real comfort. With its crisp pastry, creamy filling, and earthy flavour, it’s a recipe that fits effortlessly into everyday meals and relaxed entertaining.
