Ingredients
Method
1.Preheat oven to 220°C/425°F. Line oven tray with baking paper.
2.Melt butter with oil in large frying pan, add onion, sugar, garlic and half the thyme; cook over low heat about 20 minutes, stirring occasionally, until onion is very soft and browned lightly. Add vinegar and the water; cook, stirring, until liquid has evaporated.
3.Meanwhile, place pastry halves on oven tray; prick all over with fork. Freeze 15 minutes.
4.Top pastry halves with caramelised onion, leaving 1cm border; bake about 15 minutes or until browned. Cool.
5.Top tarts with cheese; cut each tart into four pieces; sprinkle with remaining thyme.