– 1½ pound auyama (kabocha squash), [0.7 kg] (West Indian pumpkin, or kabocha squash), seeded and sliced – 1¼ teaspoon salt, divided – 2 tablespoons olive oil – 1 large red onion – 1 tablespoon fruit vinegar – ¼ teaspoons pepper , (freshly-cracked, or ground)