1.Preheat oven to 220°C (200°C fan forced).
2.Line 21cm x 30cm (8½-inch x 12-inch) tart pan with pastry, cut away excess pastry. Line pastry with baking paper, fill with dried beans or rice. Bake 10 minutes. Remove paper and beans, bake further 10 minutes.
3.Meanwhile, heat oil in large frying pan, cook onion and half the thyme until onion is browned underneath. Turn onions to cook other side until starting to caramelise. Remove from heat, brush with honey.
4.Whisk eggs and cream in medium bowl, season
5.Reduce oven to 200°C (180°C fan forced). Pour egg mixture into tart case, add onion and cheese, scatter with remaining thyme sprigs.
6.Bake tart about 25 minutes or until firm to touch.