Brush one tablespoon of olive oil onto a baking paper lined oven tray and sprinkle with one tablespoon of castor sugar. Scatter the leaves from 3 sprigs of thyme over the sugar and top with the onion slices. Brush the onions with a tablespoon of olive oil and cook at 160°C until golden and tender (at least 45 - 60 minutes) then remove from the oven.
Butter a small individual serve frying pan and sprinkle with a little caster sugar. Sprinkle on the thyme leaves and place two cooked red onion slices onto the top.
Top with a puff pastry disc and bake at 210ºC until golden. Turn the tarts upside down onto serving plates, top with the salmon and present with the goats curd, micro herbs and radish slices. Finish with a scattering of thyme leaves, cracked pepper and several rocket flowers.
Note: fresh goats curd can be replaced by a creamy ricotta.