Pastry - makes approx 60 tarts
Mix the flour, salt and butter together on the Hobart with the paddle until breadcrumb consistency
Mix together the egg yolk and water and slowly add to the bowl, mix until fully incorporated and the pastry leaves the edges of the bowl clean
Divide into 9 blocks and chill for one hour
Roll into sheets to a thickness of 3mm then cut out with the largest cutter
To cook, spray the tart moulds with oil spray
Roll each piece of pastry to a thickness of 2mm and carefully line each mould. Prick the bottom of the shells with a fork. Lay a double layer of clingfilm in each case and fill with baking beads/pearl barley. Leave to rest in the freezer for 20 minutes
Bake at 175 fan 3 for around 12 minutes then remove the baking beads and finish cooking for a further 5 minutes until cooked through
Leave to cool then use a microplane to even the edges. Remove from the cases then brush lightly with egg yolk and return to the oven for 2 minutes to set the yolk
Filling – fill approx. 20 tarts
Drain the onions on a j cloth to remove any excess liquid
Mix together the cream, egg yolks, rosemary and salt then mix in the onions
To cook the tarts
Fill each tart case with the onion mixture, making sure to get an even amount of onions and liquid in each. Sprinkle with 10g of Mongomery cheddar cut into small 0.5cm cubes
Bake at 160 fan 3 for 12 minutes then check to ensure they are cooked. Leave to cool.
Keep in pie warmer during service and flash in the oven for 3 minutes prior to serving
Serve with rosemary cream and a salad of julienne sorrel, white chicory and finely sliced red onion (washed in water to remove the astringency) dressed with a little chardonnay vinegar and salt