Heat 2 tablespoons of olive oil in a large pot over medium heat.
Add the onion and cook until soft.
Add the garlic and cook another minute.
Add the chicken stock, Parmesan cheese rind, and a pinch of salt.
Add the escarole and allow to wilt about 2 minutes.
Cover and simmer until the escarole is the softness you prefer.
While the soup simmers, cook the pasta according to package instructions and set aside until needed.
Add the lemon juice, and taste for seasoning then season the soup with salt to taste.
Ladle onto the pasta in soup bowls and serve hot.
Notes
Escarole can be very bitter and you should remove most of the outer leaves to reveal the heart of the vegetable. The lemon juice in my recipe is for those who find escarole too bitter, but it can easily be omitted or adjusted to personal taste.