Preheat oven to 200°C. Lightly grease 12 flat-based patty pan moulds with butter and line base with baking paper.
Place butter and oil in a non-stick frying pan over a low heat. When butter has melted, add onion. Cook, stirring often, for 20-25 minutes or until onions start to caramelise. Add sugar and cook for a further 2-3 minutes or until golden. Set aside to cool. Put 2 teaspoons of onion mixture into each patty pan mould.
Using a 7cm round biscuit cutter, cut 12 circles from pastry. Place a pastry round over onion mixture, folding over excess pastry towards centre of tarts. Bake for 10-15 minutes or until pastry is golden and puffed. Carefully remove tarts from moulds. Allow to cool. Place on a platter, sprinkle with goat's cheese and top with a little chervil or parsley.
Recipe courtesy of taste.com.au
Serving size 4