Caramelised onion and mustard tart Archive

Ingredients

• 225g/8oz flour, plus extra for dusting
• 100g/3½oz butter
• 25g/1oz sugar
• 1 free-range egg
• dash milk, optional, to help bind the pastry
• 50g/2oz butter
• 1 tbsp vegetable oil
• 4 large Spanish onions, sliced
• 1 clove garlic, crushed
• salt and freshly ground black pepper
• 2 free-range eggs
• 2 free-range egg yolks
• 50g/2oz wholegrain mustard
• 150ml/5fl oz double cream
• 150g/5oz borlotti beans from a can, rinsed and drained
• 150g/5oz butterbeans from a can, rinsed and drained
• 150g/5oz broad beans from a can, rinsed and drained
• 150g/5oz cannellini beans from a can, rinsed and drained
• 1 tbsp chopped fresh mint
• 2 tsp Dijon mustard
• 1 lemon, juice only
• 1 tbsp white wine vinegar
• 100ml/3½fl oz extra virgin olive oil