In a medium sauce pot, combine the farro and 1½ cups [3 cups] lightly salted water. Bring to a boil, reduce to a simmer, and cook until the grains are tender, 12 to 15 minutes. Drain, return to the pot, and set aside. Meanwhile, prepare the sausages.

• Pat the sausages dry with a paper towel; prick in a few places with a fork, if desired.

In another medium sauce pot over medium-high heat, warm 1 tablespoon oil until hot but not smoking. Add the sausages and cook, turning occasionally, until browned but not yet cooked through, 4 to 6 minutes. Transfer to a cutting board to cool slightly, then cut on the diagonal into 1-inch-thick slices. Do not clean the pot. While the sausages are cooking and cooling, prepare the vegetables.

• Peel and coarsely chop enough onion to measure 1 cup [2 cups].
• Finely chop, press, or grate enough garlic to measure 1 teaspoon [2 tsp]. 
• Strip the kale leaves from the stems; coarsely chop the leaves.

In the same pot used for the sausages, if dry, add 1 tablespoon oil. Warm over medium heat until hot but not smoking. Add the onion and garlic, season with salt and pepper, and cook, stirring occasionally, until the onion softens, 3 to 4 minutes. Add the sausages, tomatoes, chicken broth, and 1 cup [2 cups] water and bring to a boil, then reduce to a simmer. Cook, stirring occasionally, until the sausages are cooked through, 3 to 5 minutes. 

Stir in the farro and kale (the kale in batches if needed) and cook until the kale is just wilted, 1 to 2 minutes. Remove from the heat and season to taste with salt and pepper.

Transfer the soup to individual bowls and serve.