You don't use it with anything. It's guava that's been ground up, mixed with some cane sugar, and formed into lego sized blocks. It's like a hard jelly candy. I just carry it around in a ziplock and pop a 80 calorie cube in my mouth, chew, and enjoy the yumminess. I like whole food options where I can get them.
Quince doesn't thrive here in Texas so we don't see it much.