Preheat oven to 375 degrees
Stand peppers straight up, and cut them in half lengthwise. Lay peppers face up, and carefully remove ribs and seeds. You want to have 4 pepper "bowls"
Bring a large pot of water to a boil. Add a pinch of salt and bell peppers, and parboil for 5 minutes. Drain peppers and lay on paper towels to cool
While water boils for peppers, add farro to a dry saucepan and toast over medium heat for 2 minutes. Add broth, bring to boil, reduce to simmer, and cook for 17-18 minutes. Transfer to a large bowl to cool. FARRO WILL BE SLIGHTLY UNDERCOOKED, AND THERE WILL BE A LITTLE BROTH REMAINING.
While farro cooks, melt butter in a medium skillet. Add onions and a pinch of salt and cook, over medium-low heat, for 8-10 minutes, until golden. Add garlic, and cook for 1 minute. Transfer onions and garlic to bowl with farro
Remove casings from sausage, and add to same skillet. Break into small pieces and cook for about 5 minutes. Remove and transfer to same bowl. SAUSAGE WILL BE SLIGHTLY UNDERCOOKED
Add black pepper, salt, fresh thyme, and HALF of tomatoes to bowl with farro and sausage. Combine well, taste, and adjust seasonings if needed
For 4 stuffed peppers I use an 8" x 8" baking dish. You want the peppers to touch, but not to be squished together.
Add sugar to remaining tomatoes and mix together. Spoon 3/4 of tomatoes in the bottom of a baking dish.
Lay the peppers side by side, open face up. Generously spoon farro and sausage mixture into the peppers, filling it to the top. Spoon the remaining tomatoes around the sides of the peppers, NOT ON TOP
Bake in oven for 20 minutes. Sprinkle cheese evenly across stuffed peppers, and cook for another 5 minutes.
If you halve the recipe, bake initially for 15 minutes. If you double the recipe, bake initially for 30 minutes
Remove from oven, and allow to rest for 5 minutes before serving