Step 1Toast the farro in a dry saucepan over medium-high heat, stirring frequently, until it smells nutty, about 3 minutes. Add the water and 1 teaspoon salt and bring to a boil. Reduce heat to medium-low, cover partially, and cook until the farro is tender but still chewy, about 40 minutes. Remove from the heat and let stand covered 10 minutes to allow the grain to remove any excess moisture.
Step 2While the farro is cooking, add the green beans to a medium saucepan of rapidly boiling, liberally salted water and cook just until the color brightens, about 3 minutes. They should still be crisp. Drain and plunge immediately into ice water to stop the cooking. Pat dry, cut into bite-sized pieces and set aside.
Step 3When the farro is done and while it is still warm, Add the olive oil and vinegar and stir to mix well. Add the chicken and black pepper to taste.
Step 4When ready to serve, fold in the green beans, arugula, radishes and almonds. Taste and adjust seasoning with more salt and vinegar if you think it's necessary.