2) Add the cut onion, salt, pepper and garlic powder. Bring to a boil and cover. Reduce the heat and simmer for 45 minutes. Remove the chicken and allow to cool.
3) With a hand blender, puree the vegetables in the stock. Strain the stock through a strainer into another stock pot to remove any bits. Add the chicken stock to the strained stock and put aside for later.
4) In a medium bowl, beat the eggs. Add the rapeseed oil and stock mixture and beat. Add the salt and pepper. Add the matzo meal and blend. Allow to sit on the counter for 20 to 25 minutes.
5) Remove the chicken from the bones and dice into small pieces. Put aside with the rest of the diced celery and diced carrots.
6) Bring the stock to a rapid boil. With a tbsp, scoop matzo ball mixture into the boiling water 1 tbsp at a time. If you want to roll it in a ball, oil your hands first to prevent the mixture from attaching to your hands.
7) The balls will pop to the top of the stock. Add the chicken and vegetables and cover. Simmer for 10 minutes. Add the noodles and cover for another 5 minutes before serving.