Finely chop half the mushrooms with the eschallots and garlic. A food processor works well. Line a baking tray with baking paper and spread mushroom mixture over, drizzle with oil and bake for 1 hour, stirring occasionally, until well cooked.
Finely slice the other half of the mushrooms. Melt the butter in a large saucepan and fry the mushrooms in batches until golden.
Combine both the baked and the fried mushrooms, the thyme leaves, sour cream, egg yolks and season well.
Cut a layer of filo pastry in to 6, approximately 12 x 12 cm squares, and press down into 2 x 12 hole muffin tins, so you have 6, evenly spaced filo cups filled on each tray. Repeat 4 times, brushing a little olive oil in between each layer, each time arranging the filo at a slightly different angle, until there is a strong layer of filo lining each muffin hole. The filo corners should drape like flower petals over the edges of the muffin hole. Divide mushroom mixture between filo shells.
Bake for 10-15 minutes until golden brown.
Serve warm, topped with a dollop of sour cream and a sprinkle of thyme leaves.
Notes
Lyndey’s Note: These tarts also make delightful canapes. Simply bake in 4 mini-muffin tins and cut the filo into 5cm squares.
