Combine squash, raisins, dates, lemon juice, cinnamon stick, cloves, salt, and 1 cup water in a large saucepan or Dutch oven.
Bring to a boil over medium heat.
Reduce heat to a simmer and cook, covered, 8–10 minutes.
Uncover and cook, stirring, until squash is tender and glossy and liquid is almost completely absorbed, 8–10 minutes more.
Remove cinnamon stick and cloves and discard.
Stir in lemon zest.
