1. In a large pot, set over medium heat, brown sausage until cooked through, breaking up any chunks with the back of a wooden spoon.
2. Using a slotted spoon, remove sausage to a paper towel-lined plate to drain, leaving drippings in pan.
3. Add garlic and red pepper flakes to pot and cook until fragrant, about 1 minute.
4. Add tomatoes, wine, and dried thyme and turn heat to medium high. Bring to a boil and add mussels.
5. Cover and cook 3 minutes. Remove lid, stir gently and re-cover. Cook another 3 to 4 minutes, or until most mussels have opened (discard any that do not open).
6. Remove mussels from pot with a slotted spoon or skimmer.
7. Return sausage to pot, season broth with salt and pepper and bring back to a boil for a few minutes until somewhat thickened.
8. Serve by placing mussels in large bowls and spooning sauce over.
