Preheat oven to 400 degrees. Bring a medium pot of salted water to a boil. Add stock concentrate and farro. Cook until grains are tender, 30-35 minutes. Drain and return to pot.

Wash and dry all produce. Halve and peel onion, then cut into 1/2-inch-thick wedges. Toss onion and squash on a baking sheet with a drizzle of olive oil and season with salt and pepper. Roast in oven until browned and tender, about 20 minutes, tossing halfway through.

Halve lemon. Roughly chop almonds.

Add onion, squash, almonds, cranberries, 11/2 TBSP olive oil, and a squeeze of lemon to pot with drained farro. Toss to combine. Season with salt, pepper, and more lemon (to taste).

In a medium bowl, toss arugula with a squeeze of lemon and drizzle of olive oil. Season with salt and pepper.

Divide salad between plates or wide bowls. Place farro mixture on top in a mound. Using a peeler, shave ricotta salata over plates, then serve.