I found a past foodpickle thread suggesting to cook quince down to a jam with a ratio of 4 parts quince to 3 parts sugar. So I had about 4 cups quince and mixed in about 2 1/4 cups sugar, with juice of half a lemon. It's now been bubbling away on low heat for about 45 minutes and the pieces of quince look like little darkened puffy quince balloons in a beautiful russett syrup. I tried mashing them with a potato masher, but that did not work. Has my quince jam gone to hell?
You deserve a cookie.