How to Make It
In a large saucepan, heat 1/4 cup of the olive oil. Add the garlic, onion, crushed red pepper and 12 of the sage leaves and cook over moderately high heat, stirring occasionally, until softened, about 4 minutes. Add the farro and cook, stirring, for 3 minutes. Add the water and bring to a boil. Simmer over moderate heat until the farro is very tender and most of the water has been absorbed, about 25 to 30 minutes. Drain and discard the garlic and sage leaves. Transfer the farro to a large bowl and let cool.
Meanwhile, in a large skillet, heat the remaining 2 tablespoons of the olive oil. Add the butter and cook until just beginning to turn brown, about 2 minutes. Add the squash and the remaining 12 sage leaves and cook over high heat, stirring, until browned and just tender, about 8 minutes. Add the leeks and cook until softened, about 4 minutes longer. Scrape the mixture into the farro, add three-fourths of the pickled chanterelles and toss.
Top the farro salad with the remaining Pickled Chanterelles and garnish with arugula and shaved radishes. Serve right away.
The farro salad without the garnishes can be refrigerated overnight.