Preheat oven to 400 degrees F.¬† Pop sheet tray into the oven to warm up.
Set a large stock pot over medium heat.¬† Add butter, olive oil, garlic and thyme and gently saut√© until fragrant.¬† Add carrots, onion and celery, season with salt and cook for 5-7 minutes .¬† Tie up peppercorns, parsley stems and bay leaf in a piece of cheesecloth and add to pot.¬† Pour in chicken broth and bring to a boil then reduce heat to simmer while you work on meatballs and tortellini.
Caramelize diced onion a saut√© pan with a little olive oil over medium heat.¬† Split the sausage links down the middle and empty the meat into a large mixing bowl, discard the casings.¬† Add the caramelized onion, fresh breadcrumbs, egg, fresh thyme, ¬ľ cup parmigiano and chopped parsley.¬† Fold together, but do not over work, and season with a few turns of black pepper.¬† Take the hot sheet tray out of the oven.¬† Add a drizzle of olive oil and then use a small ice-cream scoop to drop meatballs onto tray ‚Äď they should be about 1 inch in diameter.¬† Sprinkle tops with remaining grated parmigiano and bake in the oven for 15-20 minutes.¬† Boil tortellini in salted water until al dente, drain and set aside.
Once meatballs are done, scrape into pot of chicken broth and add tortellini so everything is back in the pot.¬† Bring to a gentle simmer and cook for 2-3 minutes to allow flavours to come together.¬† Give it a final season and serve in shallow bowls with a small shower of parsley.
Edited: October 15th, 2009