Place chickpeas in medium bowl, cover with cold water; stand overnight.

Make green onion crisps. Finely chop trimmed onions. Combine onion, flour, yeast, salt and sugar in medium bowl; make a well in the centre. Stir in oil and enough of the water to mix to a soft dough. Knead dough on floured surface about 5 minutes or until smooth and elastic. Place dough in large oiled bowl, cover; stand in warm place about 1 hour or until dough doubles in size.

Preheat oven to 220°C/425°F. Oil oven trays, place in oven.

Turn dough onto floured surface; knead until smooth. Divide dough into 16 equal pieces. Roll each piece into long ovals about 3mm (⅛ inch) thick; place on hot trays.

Lightly coat with olive-oil spray. Sprinkle with extra salt. Bake about 5 minutes or until browned lightly and crisp. Reduce oven temperature to 200°C/400°F.

Chop peeled pumpkin coarsely. Place pumpkin, in single layer, in baking-paper-lined large shallow baking dish; spray pumpkin with oil. Roast, uncovered, about 45 minutes or until tender. Cool.

Meanwhile, rinse and drain chickpeas. Place chickpeas and the water in large saucepan; bring to the boil. Boil, uncovered, about 45 minutes or until chickpeas are tender. Drain chickpeas over a medium heatproof bowl; reserve cooking liquid.

Meanwhile, peel and quarter garlic. Blend or process chickpeas with 1 cup reserved cooking liquid, garlic, pumpkin, juice, tahini and oil until smooth (add a little more of the reserved cooking liquid, if you need, until hummus is a creamy consistency). Season to taste.

Drizzle hummus with extra oil, serve with green onion crisps.