In a large bowl, toss zucchini and 1/2 teaspoon salt; let stand for 10 minutes. Squeeze zucchini dry. Stir in the eggs, onion, matzo meal, pepper and remaining salt.
In a large skillet, heat oil over medium heat. Drop batter by tablespoonfuls into oil; press lightly to flatten. Fry for 2 minutes on each side or until golden brown. Serve with sour cream if desired.