For the spiced lamb tart with filo, clarify the butter: put the butter and sliced garlic in a heavy saucepan over low heat. Melt gently. Skim off all the froth from the surface. You will then see a clear yellow layer on top of a milky layer.
Carefully pour the clear fat into a bowl or jug, leaving the milky residue in the pan. Discard the milky residue. Set aside the clear fat.
Preheat the oven to 180C/350F/Gas 4.
Place the lamb mince in a roasting tray and cook in the oven until it turns a rich roasted colour. This will take about 20 minutes.
Heat the stock, star anise and cumin in a medium saucepan and reduce until a rich cumin glaze forms (about 50ml/1¾fl oz in volume). Remove the star anise and set aside.
Heat a large frying pan, add the oil and fry the onion, chilli and garlic until soft.
While the onion is cooking, butter the tart rings and cut the filo into 10 squares slightly larger than the tart rings.
Lay one sheet of the filo on a tray, evenly brush with the clarified garlic butter and repeat the process three times, each time laying the squares at different rotation points, buttering between each layer.
You should end up with a star shape. Lay this into a tart ring and push the filo into the corners, line with crumpled parchment paper then fill with baking beans or rice. Repeat to fill the other ring. Any remaining filo should be wrapped carefully and placed in the fridge for use in another recipe.
Bake for 15 minutes, or until the base of the filo is fully cooked.
Remove from the oven and leave the baking beans or rice in until cool.
Dice the cucumber into small neat cubes and lightly season with salt to draw out the moisture.
Mix the mince, glaze, onion mixture, mint, coriander and salted cucumber together and add salt and pepper to taste.
Remove the tarts from the rings, then fill with the lamb mixture. Put on a baking tray, and top with a sheet of filo for each tart, scrunching it lightly to make a pie lid for the tart. Bake for five minutes.
For the dressing, combine all the dressing ingredients.
Serve the tart with the yoghurt dressing.