Cut tops off of the tomatoes (large enough to use as a cap).
Scoop out inside ribs and pulp, reserving for later use.
You should have a tomato cup suitable for filling and its cap, both of which will be used.
In a medium saucepan over medium heat, sauté shallot and garlic in 1 T olive oil until tender (2-3 minutes).
Add enough chicken stock to the reserved tomato pulp to equal two cups.
Add tomato pulp/chicken stock mixture and barley to saucepan.
Bring to a boil and reduce to a simmer.
Salt and pepper to taste, cover and simmer until barley is al dente, about 15 minutes.
Preheat oven to 400 degrees F.
In a small skillet over medium high heat, sauté sausage, breaking up with a wooden spoon until browned.
In a large mixing bowl, combine barley, sausage, parsley, and parmesan cheese.
Check seasonings and adjust as necessary.
Salt & pepper the insides of tomatoes, then fill with barley mixture.
Be sure to not pack the stuffing tight.
Set stuffed tomatoes aside.
Use remaining olive oil to grease 11x7 baking dish.
Add extra barley mixture to the bottom of baking dish and spread out evenly.
Add stuffed tomatoes to baking dish, nesting down into the stuffing.
Replace the tomato caps and drizzle another ¼ C of chicken stock over contents of the baking dish.
Roast for 30 minutes, until tomatoes are soft and the skins start to split.