Quince Soda Syrup

Place quince, sugar, lemon juice, and salt in a medium saucepan along with 4 cups water. Cover and bring to a simmer over medium heat; let simmer for 2 hours.

Add more sugar, if desired, and let cool. Transfer to refrigerator and let chill overnight.

Strain and discard solids. Transfer syrup to an airtight container and keep refrigerated until ready to use, up to 2 weeks. To serve, fill a 16-ounce glass with ice cubes and add 1 1/2 ounces syrup; top with seltzer and stir to combine.