Golden matzo balls

1 3-pound kabocha Squash
4 large Eggs
1/4 cup (1/2 stick) pareve Passover Margarine, melted
2 teaspoons Sugar
1-1/2 teaspoons kosher Salt
Large pinch of ground Nutmeg
Large pinch of ground Ginger
1 cup matzo meal
2 large Onions, peeled

1. Pierce Squash in several places with tip of small knife. Cook in microwave on high for 10 minutes. Turn over, cook until very tender, about 10 minutes longer. Cut in half horizontally. Scoop out seeds; cool completely. Spoon squash into bowl. Mash with fork or potato masher. Place 1/2 cup (packed) mashed squash into medium bowl (reserve remaining squash for another use). Add Eggs, Margarine, Sugar, Salt, Nutmeg and ginger; whisk to blend well. Mix in matzo meal. Cover and refrigerate overnight.
2. Bring large pot of salted water to boil over medium-high heat. Add Onions to pot. Drop matzo ball mixture by heaping tablespoonfuls in 16 mounds onto sheet of foil. Using moistened hands, shape mounds into smooth balls; drop into boiling water. Cover pot tightly. Boil matzo balls until very tender and evenly colored throughout, adding more boiling water to pot occasionally, about 2 hours. Transfer matzo balls to dish in single layer.