Combine all the meatball ingredients in a large bowl and mix with your hands.
Roll the mix into 1-inch meatballs and place them on a plate to chill.
Heat a large pot or dutch oven over medium-high and add a Tbs of oil.
Brown the meatballs in two batches until they have good color.
Add the stock and crushed tomatoes to the pot and bring to a boil.
Reduce the heat to medium and let simmer for about 20 minutes.
Add the pasta and spinach to the pot and stir.
Taste and adjust seasoning if necessary, adding fresh lemon juice if desired.
Ladle into bowls and garnish with fresh parmesan.
