Combine the farro with the water, olive oil, and salt. Bring to a boil, reduce to a simmer, cover, and cook for 25 minutes. The farro should be mostly softened but will finish cooking in the soup.
Finely mince the onion, celery, and garlic. I like to chop, but you could easily pulse in a blender. Heat a pot over medium heat. Add the olive oil, followed by the onion/celery. Cook until the mix has softened and beginning to turn golden. Add in the garlic, cooking for a minute more. Next, stir in the tomato paste and cook for another minute or so.
Add in the tomato sauce, chickpeas, and 2 cups of water. Bring to a boil, reduce to a simmer, stir in the partially cooked farro and continue to cook until the sauce has thickened and the farro is cooked through; about 10 to 15 minutes. If the soup is looking too thick, add ½ cup of water at a time.
While the farro is cooking, make the oil. Place the chili flakes in a heat-safe bowl that’s large enough to hold the hot oil too. Place the oil in a pan and heat over medium heat until the oil is hot (should appear to shimmer). Carefully pour the oil over the crushed red pepper and let cool.
Once the farro is done, stir in the parmesan. Taste and add more parmesan and/or salt as desired. Divide into two bowls and top with a small drizzle of oil and fresh dill.