Peel and dice the sweet potato into small cubes. Slice the scallions and roughly chop the spinach, separating stems from leaves.
Roast or pan-cook the sweet potatoes.
To roast: Toss cubes with olive oil and bake at 400°F (200°C) for 20–25 minutes until tender and lightly browned.
To pan-cook: Heat half the olive oil in a skillet over medium heat and cook the sweet potatoes, turning occasionally until tender and golden.
Cook the quinoa according to package instructions. Usually combine quinoa with twice the amount of water, bring to a boil, then simmer covered for about 10 minutes until the water is absorbed and the grains open.
In a small skillet, heat the remaining olive oil. Add scallions and spinach stems and cook for 1–2 minutes until softened. Add spinach leaves and cook until wilted.
If needed, briefly warm the steak in a skillet over medium heat and slice thinly.
Assemble the steak quinoa bowl by dividing quinoa between two bowls. Top with spinach mixture, sweet potatoes, sliced steak, and raisins.
Whisk together lemon juice, tahini, olive oil, and honey to make the dressing. Drizzle over each bowl before serving.