Two things I always make as soon as I get my hands on quinces are Membrillo and Quincemeat. Membrillo is the perfect give away treat, is delicious with cheese and costs a fortune if you have to buy it in the shops. Quincemeat provides a good build up for the festive season, and is a great excuse to eat mince pies in October. A note on preparing quinces - they are a bugger to peel, especially the small, wild knobbly ones so I cook mine whole for my membrillo recipe, then pull off the flesh. However if you have those show-offy perfect, plump quinces then it's easier to peel and core them first, which saves sieving them. The horrible little runt quinces I make into quince jelly to spread on my toast and to glaze fruit tarts.