Cajeta de Membrillo. Step 3: Don't toss out the good stuff.

Don't be overly concerned about leaving some peel, nor digging out the ombligo and stem end.

Sculpt out the stem and seed from the fruit. Save this material. You can also find the hard parts with the knife and slice big chunks of fruit away from the seed and stem. If you have a good sharp knife you can do the sculpting. The cube of seed in the upper left corner is what you get when you don't sculpt.

Agua de Membrillo

Toss the peel and seed cores into a big pot. Add the water from the boiled Quince. Add more water. Add sugar proportionate to the water and your preference for sweet. I prepped the membrillo in a 7 quart pot, and used that for the agua. Add some sticks of canela, the limón halves. I squeezed in a tiny blood orange for added color. Boil boil sin toil ni trouble until the kitchen smells good from the canela and the fruit has begun to disintegrate, and the volume of the water is reduced somewhat.
Let it cool for a while then pour through a strainer into a pitcher. Slice another blood orange thinly to garnish each serving. You can drink it warm or chilled, dilute with water if you cooked it too syrupy. Agua de membrillo is some delicious stuff. This would work well with fresh or dried figs, too. I imagine you could freeze this and one hot summer day, defrost it and serve icy cold, but we drank the whole pitcher in a single tamalada.