Mary Berry caramelised onion tart lovers, this is the recipe that brings rustic charm, sweet-savoury flavour, and classic British baking together in one irresistible dish. Whether you’re a devoted Mary Berry fan or simply want a reliable tart recipe that works every time, this guide covers ingredients, steps, health benefits, serving ideas, and expert-level tips to guarantee delicious results.
This recipe is also perfect for strengthening your collection of Mary Berry favourites—be sure to explore more inspirations in our Mary Berry Recipes category at Food Fables:
Why This Caramelised Onion Tart Works
Mary Berry’s savoury bakes have a reputation: simple techniques, big flavours, and timeless appeal. This tart is no exception. Slowly cooked onions become beautifully sweet, the pastry stays crisp, and the custard-style filling adds a subtle richness without overpowering the dish. It’s ideal for:
- Weeknight dinners
- Picnics
- Brunch
- Potluck gatherings
- Seasonal entertaining
Plus, caramelised onion tart is extremely versatile—serve it warm or cold, with a side salad, roasted vegetables, or even soup.
Ingredients You’ll Need
For the Pastry
- 175g plain flour
- 85g cold butter, cubed
- Pinch of salt
- 1–2 tbsp cold water
For the Filling
- 3–4 large onions, thinly sliced
- 25g butter
- 1 tbsp olive oil
- 2 eggs
- 150ml double cream (or half cream, half milk)
- Salt & pepper
- Optional: thyme, grated cheese, or balsamic drizzle
Step-by-Step Method
1. Prepare the Pastry
Rub the butter into the flour until you achieve a breadcrumb texture. Add the cold water gradually until the dough comes together. Wrap and chill for 20–30 minutes.
2. Caramelise the Onions
Heat butter and oil in a pan on low heat. Add the onions and cook slowly for 25–35 minutes until golden and soft. The slower the cook, the sweeter the flavour—this is the foundation of the tart. A splash of balsamic vinegar can intensify the caramelisation if desired.
3. Blind Bake the Crust
Roll out the chilled pastry and line a tart tin. Prick the base with a fork, line with baking paper, add baking beans, and bake for 15 minutes at 180°C. Remove beans and bake for another 5 minutes until lightly golden.
4. Fill and Bake
Whisk eggs, cream, salt, and pepper. Spread the caramelised onions evenly over the base, pour in the custard mix, and bake for 25–30 minutes until set and lightly golden.
Health Benefits of Caramelised Onion Tart
Although indulgent, this tart offers some surprising health benefits:
✔ Rich in Antioxidants
Onions are naturally high in quercetin, a powerful antioxidant associated with reduced inflammation and improved heart health. According to research from Healthline, onions may support heart function and healthy cholesterol levels. (External resource: )
✔ Protein and Calcium from Eggs & Cream
The filling contains nutrient-dense ingredients that support bone health and energy levels.
✔ Can Be Made Healthier
Swap cream for half milk, use wholemeal pastry, or add sautéed spinach or mushrooms to boost fibre and nutrients.
Serving Suggestions
- Pair with a fresh green salad tossed with lemon vinaigrette.
- Serve alongside roasted vegetables for a hearty vegetarian dinner.
- Add grilled chicken if you prefer a protein boost.
- Try a dollop of chutney or relish for extra tang.
Expert Tips for Perfect Results
- Low and slow is essential—caramelising onions too quickly results in bitterness.
- Keep pastry cold to avoid shrinkage.
- Season generously; onions become sweeter in the oven, so salt balances everything.
- Let the tart rest 10 minutes before slicing for cleaner cuts.
Variations Worth Trying
Cheese Lovers:
Add 50–75g of grated Gruyère or cheddar to the filling.
Herb Boost:
Fresh thyme or rosemary complements the sweetness perfectly.
Vegan Version:
Use vegan pastry and replace eggs/cream with a blended tofu or cashew mixture.
Conclusion
The Mary Berry caramelised onion tart is the perfect combination of simplicity and sophistication. With its sweet onions, crisp pastry, and creamy filling, it fits beautifully into any meal plan. Whether you follow the classic version or customise it with herbs or cheese, this tart is guaranteed to become a repeat favourite in your kitchen.