Whisk eggs, egg white and salt in a medium bowl. Whisk in matzo meal, oil and water. Cover and chill for at least 1 hour or overnight.
Fill a large pot with chicken broth, ginger, garlic, lemon juice, lemon peel, and chicken breasts. Bring to a boil, then reduce heat to medium low and allow to simmer partially covered for 15 minutes. Turn off the heat, cover and steep for another 20 minutes.
Once chicken is cooked through, remove the ginger, garlic and lemon peel and discard from the broth. Shred the chicken breast and keep aside.
Meanwhile, roll the chilled matzo dough into teaspoon sized balls.
Bring the broth back up to a boil and add in the sweet potato, carrots, celery, and onion.
Reduce the heat to medium low, and add the matzo balls to the simmering broth. Cover and cook for 15 minutes. Do not lift the lid: the broth must simmer rapidly to allow the matzo balls to expand properly.
Add the kale and the shredded chicken, and cook uncovered, until the kale wilts and softens, about 2 to 3 minutes. Ladle into bowls, sprinkle with parsley and serve.