Heat the extra-virgin olive oil and 1 tablespoon butter in a large pot; add the shallots. Saute the shallots until they are translucent. Add the farro, stir and lightly toast and coat with the butter. Add 1 cup Chianti and let it reduce completely, stirring constantly. Ladle 1/2 cup vegetable stock at a time into the farro. Continue stirring, adding more vegetable stock as it evaporates. Repeat the process until the stock is gone. Continue the process using the remainder of the wine. Cook for another 12 to 15 minutes or until the farro is al dente. Stir in the grated Parmigiano cheese and the remaining butter. Transfer the risotto to a warm bowl and serve immediately.