And this is what I did...

Stuffed Quinces (Dolmeh-e Beh)
4 large quinces
1 onion, finely chopped
chopped cooked flat rib of beef
2 Tbsp. oil
1 tbsp. tomato paste
vinegar or lemon juice
1 tsp. cinnamon
1 Tbsp. Butter,

Wash quinces, removing fluffy layer, halve and hollow out as best you can (difficult I thought) saving any useful flesh (not pip)
Brown onion , add meat in 2 Tbsp. oil. Add tomato paste, 2 Tbsp. vinegar or lemon juice, remaining quince flesh, salt, pepper, and 1tsp cinnamon. Mix thoroughly. Stuff as much as you can into quinces. Place into an oven proof dish, pour around some good, flavoursome homemade stock. Cover with foil and bake 40 mins at 190 C.
Then mix a little lemon or vinegar, sugar and butter and pour over quinces and return to oven,briefly.

Serve with bread, yogurt, and fresh herbs.
Jane Grigson and Maideh Mazda had a good hand in this, not to mention centuries of Persians.