Garden beetroot and roscoff onion tart

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

Credit: Royal Gardens on a Plate

• serves

  2

• prep

  1 hour

• cook

  1 hour

• difficulty

  Mid

Ingredients

For the pastry base

• 300 g (10½ oz) ready-rolled puff pastry, chilled then rolled to 3 mm thick

For the beetroot

• 300 g (10½ oz/about 6 small) golden or chioggia beetroot, scrubbed clean
• pinch of sea salt
• 2 pinches of black pepper
• 20 g (¾ oz) unsalted butter, warm

For the onion jam

• 10 g unsalted butter
• 200 g (7 oz/about 1) rose de roscoff onion (or red onion), sliced
• pinch of sea salt
• pinch of black pepper
• 2 tsp Jerez vinegar (or sherry vinegar)

To build the tarts

• 1 egg yolk, beaten with 2 tsp water for an egg wash
• pinch of black pepper
• 1 tsp orange and thyme dried powder (optional; see Note)

For the Jerez vinaigrette

• 4 tsp Jerez vinegar (or sherry vinegar), boiled for 30 seconds
• 40 ml (1½ fl oz) good-quality olive oil
• pinch of sea salt
• pinch of black pepper

To serve

• 150 g (5½ oz) mixed salad leaves
• 60 g (2¼ oz) goat's cheese or cottage cheese

Chilling/freezing time 1 hour

Instructions

For the pastry base, line a baking tray with greaseproof paper. Cut the pastry into two 13 cm (5 in) discs using a chef’s ring or a small plate and place on the lined baking sheet. Transfer to the fridge, or ideally the freezer, for at least 1 hour, to prevent the pastry being sticky.

Preheat the oven to 180°C (160°C fan-forced/Gas 4).

To prepare the beetroot, cut the root off each one. Using a mandoline set to a thickness of 1 mm, slice into thin discs and transfer to a bowl (see Note). Season with salt and pepper. Stir in the warm butter to ensure each slice of beetroot is evenly coated.

To cook the beetroot, place a 9 cm (3½ in) metal ring in a 12 cm (4½ in) blini pan. Layer the seasoned beetroot discs inside the ring in a rosace pattern 3 layers deep. The metal ring will facilitate the building of the beetroot and keep it upright and in a perfect circle. Repeat this with the other blini pan and metal ring. Cut a circle of baking paper to the same size as the blini pan. Lift the metal ring off the beetroot and lay the baking paper on top of the beetroot rosace, then press the ring back over the rosace. (By placing the ring over the paper you will trap the steam trying to escape, which will keep the beetroot beautifully moist; see Note.)

Cook the beetroot rosaces on medium heat for 2 minutes, until the sides start to bubble. Some juices from the beetroot will boil in the pan – this is important as it speeds up the cooking of the beetroot in the oven and gives a nice light caramelisation to the beetroot.

Transfer the beetroot to the oven for 10-12 minutes. Remove from the oven, leave to rest and cool completely. Lift off the rings and greaseproof paper from the cooled beetroot rosaces and turn them out on to a small plate (the coloured side, with its golden rosace pattern will be facing upwards). Set aside.

Meanwhile, for the onion jam, in a saucepan over medium heat, melt the butter and add the onion, salt and pepper. Cook for 35-40 minutes, covered with a lid, until softened but not caramelised. Stir every 5 minutes to prevent the onion from burning. Deglaze the pan with the vinegar, scraping any browned bits from the bottom with a wooden spoon, and boil for 20 seconds. Taste and adjust the seasoning if necessary. Leave to cool completely.

To build and cook the beetroot tarts, divide the onion jam equally between the two pastry discs and with the back of a spoon spread the onion to a thin layer leaving a gap of 1 cm (½ in) around the edge. Lightly brush the pastry edges with a thin coating of egg wash. Sprinkle them with the black pepper and powdered orange and thyme, if using. Using a palette knife, lift each golden rosace into the centre of each pastry base. Place a piece of baking paper over each of the tarts and place a cooling rack on top of them. Transfer to the oven for 20 minutes, or until the sides of the pastry are golden-brown. The baking paper and cooling rack on the tarts help keep the moisture in the beetroot; it will also ensure the pastry rises evenly and the beetroot slices do not curl whilst cooking.

To make the Jerez vinaigrette, mix all the ingredients together in a small bowl. Taste and adjust the seasoning, if necessary.

To serve, dress the leaves with half the vinaigrette and arrange on each plate. Scatter the cottage cheese over the salad. Brush the remaining vinaigrette over the beetroot tarts to give flavour and a beautiful glaze and serve immediately.

Notes

• To make your own dry orange zest and thyme in an oven at 100°C (80°C fan-forced/Gas ¼) for 1 hour, then blitz to a powder

• Once the beetroot has been cut or sliced, use within 20 minutes to prevent discolouration or oxidation.

• To ensure the success of this dish it is crucial to cover the beetroot with the circle of paper secured by a ring in order to keep all the moisture and the flavour.

See more from Raymond Blanc in Royal Gardens On A Plate, on SBS and SBS On Demand.

Cook's Notes

Oven temperatures are for conventional; if using fan-forced (convection), reduce the temperature by 20˚C. | We use Australian tablespoons and cups: 1 teaspoon equals 5 ml; 1 tablespoon equals 20 ml; 1 cup equals 250 ml. | All herbs are fresh (unless specified) and cups are lightly packed. | All vegetables are medium size and peeled, unless specified. | All eggs are 55-60 g, unless specified.