Preheat oven to 450 degrees.
Combine all of the chopped vegetables in a large roasting pan.
Whisk together the olive oil, minced garlic, basil, oregano and fennel seeds.
Pour over the vegetables and toss to coat. Season with salt and pepper.
Pour chicken broth over vegetables. Cover with foil and bake for about 30 minutes, or until vegetables are just tender.
Meanwhile, brown sausages in a large skillet over medium heat. They do not need to be cooked all the way through, just browned.
Remove from skillet and slice into thirds.
Remove foil from vegetables and add sausages to pan.
Pour in balsamic vinegar and give everything a good stir.
Return the pan to the oven, uncovered, for 20-30 minutes, or until everything is browned as the sausages are cooked through.