1.Preheat oven to 220°C (200°C fan-forced). Grease and line two oven trays.
2.Melt butter in large frying pan, cook fennel until browned lightly. Add rind and juice, bring to the boil. Reduce heat, simmer, uncovered, about 5 minutes or until fennel is caramelised and tender.
3.Cut pastry sheet into four squares, place on oven trays. Remove fennel from pan, leaving behind the pan juices, divide among pastry squares. Bake about 20 minutes or until pastry is browned.
4.Meanwhile, return pan juices to the boil. Reduce heat, simmer, uncovered, until sauce thickens slightly.
5.Serve tarts drizzled with sauce and sprinkled with thyme.
Fennel using a smell test: a sweet, not sour, smell indicates freshness. Look for upright green fronds and a bulb that’s not bruised or slimy. Can store for up to 3 days in a plastic bag in the refrigerator. Fennel loses its flavour quickly, so use as soon as possible. Remove the outer layer of the bulb as it can be tough. Trim a very thin slice from the base then cut the bulb in half from top to bottom. Use a small sharp knife to gouge the pyramid-shaped core out of the base. Slice fennel as required. Fennel goes well with spring onion, peppery salad leaves, orange, lemon juice or parmesan. Slice very thinly. Trimmed and halved fennel in boiling water for about 5 minutes or until tender. Trimmed and halved fennel for about 5 minutes or until tender. Fennel is suitable to be cooked in a microwave oven. for 2 to 4 minutes. Cook thick slices slowly for wonderfully sweet results. thick pieces until soft and caramelised. Drizzle with a little balsamic vinegar near the end of the cooking time. in white wine or other cooking liquid. Fennel will absorb the flavour of the braising liquid.