Raymond Blanc served up a tasty beetroot and roscoff onion tart for the Autumn on Kew on a Plate.

Raymond says: “In this delicious starter the beetroot is cooked from raw, rather than being blanched first, which concentrates its wonderful earthy flavour.”

The ingredients for the pastry base: 300g ready-rolled puff pastry, chilled then rolled to 3mm thick.

For the beetroot: 300g (about 6 small) Golden or Chioggia beetroot, scrubbed clean, pinch sea salt, 2 pinches black pepper and 20g unsalted butter, warm.

For the onion jam: 10g unsalted butter, 200g Rose de Roscoff onion (about 1), sliced, pinch sea salt, pinch black pepper and 2 tsp Jerez vinegar (or sherry vinegar).

To build the tarts: 1 egg yolk, beaten with 2 tsp water for an egg wash, pinch black pepper, 1 tsp orange and thyme dried powder (optional), to make your own dry orange zest and thyme in an oven at 100C/80C Fan/Gas ¼ for 1 hour, then blitz to a powder.

For the Jerez vinaigrette: 4 tsp Jerez vinegar, boiled for 30 seconds, 40ml good-quality olive oil, pinch sea salt and pinch black pepper.

To serve: 150g mixed salad leaves and 60g cottage cheese.

See Raymond’s recipes from the series in the book titled: Kew on a Plate with Raymond Blanc (Kew Gardens) available from Amazon now.