Preheat oven to 425F. In a large bowl, whisk together 2 teaspoons tamari, 1 tablespoon honey, ginger, and oil. Add chicken and toss to coat. Transfer to a parchment-lined baking sheet in a single layer and roast for 10 minutes, until cooked through
Meanwhile, fill a large pot with water and fit with a steamer basket. Bring to a boil and add broccoli. Steam for 3 to 4 minutes, until tender-crisp.
Meanwhile, whisk together almond butter, remaining 2 teaspoons tamari, remaining 1 tablespoon honey, vinegar and Sriracha, if desired. Divide chicken and broccoli among serving plates and drizzle broccoli evenly with almond butter sauce.