The night before cooking the stew, place the dried chickpeas in a large bowl and cover with the water. Transfer to the refrigerator and leave to soak overnight.
The next day, drain the chickpeas. Heat a large sauté pan (for which you have a tightly fitted lid) over medium heat for one minute. Transfer the drained chickpeas and baking soda to the pan. Shake the pan to distribute the baking soda amongst the chickpeas and cook, stirring constantly for 5 minutes.
Add the chicken broth, tomatoes, onion, garlic, salt, black pepper, and cumin and to the pan. Increase the heat to high and bring to a boil. Once boiling, cover the pan, reduce the heat to low, and cook the chickpeas and vegetables for 45 minutes.
In a fine mesh colander, rinse the farro well and drain. Add it to the pan, cover, and cook an additional 45 minutes.
To finish the stew, stir in the freshly squeezed orange juice, honey, butter, and fresh cilantro. Let rest 10 minutes, uncovered, and serve warm.