Membrillo (the name of quince in Spanish) is what I've generally heard quince paste called when it is classically paired with manchego cheese, but I think that the term is really dulce de membrillo, meaning candied quince. It's true, it takes a lot of sugar to make quince paste, and in some places people roll the paste in more sugar to eat as a dessert.
I have made membrillo before and shared the recipe here, but I think I've learned a few things by making it again.
1) Using a scale is the best way to figure out the fruit to sugar ratio. Most recipes call for cooking the quince, using a sieve or food mill to make a sauce, and then figuring out how many cups of mushed fruit one has in order to figure out how many cups of sugar you need. Total mess. It's really just a one to one ratio of fruit to sugar in order to get the paste to set. So just figure it out before you have to mess up measuring cups and spoons and you lose half the fruit. Sometimes I've used less sugar, but I always worry that I'm pushing it on being able to form a good gel and the paste having a long enough shelf life. The stuff is sweet, no doubt about it, so go ahead and use all the sugar.
2) Use no more than 6 pounds of fruit. That's what they always say about jams, because the fruit and sugar both melt turn mostly into water that has to be driven off by heat before the jam can gel and set properly. The more you have, the longer it will take to drive the water off and in the process the pectin can be lost, resulting in a bad set. Plus, it will take forever to stir. Believe me, six pounds of quince and six pounds of sugar results in more membrillo than most people ever want. You'll end up begging people to take some even after the holidays are over. Four pounds is probably more reasonable.
3) Give the fruit time to oxidize so that it will turn a deep orange or rose color. My last batch was a pretty orange color after much cooking, but it could have been a deeper color if I'd let the cooked quince rest in the pot for eight hours or so, according to some cooks. I've used a crockpot to cook the quince before, but it seems like a hassle to then turn it out into another pot for the rest of the cooking. I've also cooked the quince whole to get all of the pectin out of the seeds and then tried to sieve them out. Not worth it; the quince gels just fine with only the skin on and that can be mixed in with a stick blender quite easily.
4) Be prepared to stay at the cooking pot for a long time- up to two hours. Use an apron and have lots of towels around. The jam cooks down and starts to pop like an active volcano spewing out some sort of napalm. It sticks and burns, so have a damp cloth around to wipe off the burning quince paste and be prepared to wrap your stirring hand in a cloth as the paste starts to pop. I got some pretty bad burns from the popping paste and a blister from the wooden spoon I was using to stir. Luckily Chris stepped in with his longer arms and took a turn stirring for a while. Keep the burner turned as low as you can while still cooking the fruit and sugar mixture down.
5) When you can slide a spoon through the mixture and see the bottom of the pan, the membrillo is a deep orange or rose color and it has stopped popping so viciously in the pan, turn it out onto the prepared parchment paper and spread it around. If it gets too sticky and cooked down, it can be hard to get out of the pan.
6) Leave the membrillo to cool completely in the pan before turning it out and cutting it into squares. Wrap tightly in plain parchment paper, then in plastic and it will keep in the refrigerator for at least 3 months.
Finally, the recipe!
Quince, sugar, lemon peel and juice. Butter or vegetable oil and parchment paper.
1) Cut parchment paper to fit one or more flat bottomed pans. Lightly grease parchment paper. Some people grease molds for quince paste. If you have trouble getting a thick portion of paste to set, try leaving it in warm oven or putting it a into food dehydrator until the middle is set.
2) Gather quince, wash and rub all the fuzzy fur off. Cut quince into quarters with a sharp knife and take out the seeds. Determine how many pounds of quince you have.
2) Cook quince and lemon peel in enough water to cover it by half an inch or so until the fruit is tender (30-45 minutes). Use a heavy bottomed pot to keep the jam from burning after sugar is added later. Make sure the pan is large enough to give the jam space to bubble and be stirred.
3) Drain quince (some people keep the water for jelly, some highly energetic people). Put quince and lemon peel back in pot and blend with a stick blender until a fine, applesauce like texture is formed. Alternately, put softened quince through sieve or foodmill.
4) Add juice of 1/2 to 1 whole lemon (depending on how much quince you have). Example- 2-4 pounds, half a lemon, 5- 6 pounds, a whole lemon.
5) Stir in sugar, a 1 to 1 ratio with quince. If you don't know how many pounds you have, use the measuring cup method with the quince sauce you've just made.
6) Cook on medium high until the paste thickens, then turn down to low. Stir constantly and vigilantly. As the paste thickens it will burn easily.
7) Watch for color changes and thickness. This can take anywhere from 45 minutes to two hours in my experience.
8) Turn paste out into prepared pan/pans. Let cool thoroughly. Turn out finished brick of dulce de membrillo and cut into squares or rectangles for storage.
9) Eat with cheese, put in a sandwich, or melt some in a pan with vermouth and ham after browning chicken in a pan with butter, garlic and onions.