Asparagus, caramelised onion and Gorgonzola puff tart – Food & Home Magazine

Ingredients

• 1 x 400g roll puff pastry, thawed
• 1 egg, beaten
• 40g butter
• 4 large onions, thinly sliced
• 30ml (2 tbsp) brown sugar
• 30ml (2 tbsp) balsamic vinegar
• salt and freshly ground black pepper, to taste
• 400g fresh asparagus, trimmed and blanched
• olive oil, to brush
• 75g Gorgonzola
• handful microherbs, to garnish