Peel and halve quince, remove cores (reserve skin and cores) and place in acidulated water until required.
Combine reserved peel and cores with sugar, spices and 2 litres water in a large saucepan, stir over medium-high heat until sugar dissolves. Bring to the boil, cook until ruby-coloured and infused (25-30 minutes), then strain (reserve syrup and solids separately).
Preheat oven to 80C or lowest setting. Place quince in a deep roasting pan large enough to fit snugly in a single layer, then cover closely with a layer of muslin or baking paper. Pour over syrup, spread reserved skins and cores over the top, cover with a double layer of foil and roast until tender and rosy in colour (10-12 hours). Remove and discard foil, skin, cores and muslin.
For saffron custard, bring cream and saffron to the simmer in a small saucepan over medium-high heat. Meanwhile, whisk yolks, sugar and cornflour in a bowl to combine. Add cream mixture, whisk to combine, then return to pan and stir continuously over low heat until mixture thickly coats the back of a wooden spoon (2-3 minutes). Strain into a bowl over ice, add nutmeg to taste and whisk occasionally until chilled. Serve with slow-baked quince and a little syrup, scattered with pistachios.
This recipe is from the July 2011 issue of Australian Gourmet Traveller.