Preheat the oven to 400 degrees Fahrenheit.
In a large bowl, toss the Brussels sprouts, butternut squash, and onion slices with 1 tablespoon of oil. Season with salt and pepper.
Spread the vegetable evenly on a baking sheet (you may need to use two baking sheets if using one is too crowded) and bake for 25 minutes. Set aside and let it cool slightly.
While the vegetables are roasting, cook the farro according to package directions.
In a large bowl, mix together the farro, dried cranberries, and sliced almonds.
In a small bowl, whisk together the dressing ingredients, pour over the farro, and stir to combine. Add the roasted vegetables, and gently mix everything.