Heat 1 teaspoon of olive oil in a large sauté pan. Add steak and season to taste with salt and pepper. Cook until steak is medium to medium well or whatever your temperature preference is. Remove from heat and set aside.
In a large salad bowl add baby spinach, onion, blue cheese, 1 tablespoon of olive oil, and balsamic vinegar. Toss until salad is completely mixed and coated with dressing. If you need more dressing add a little more olive oil and balsamic vinegar to taste. Divide among 4 plates and enjoy.
You can also serve this with homemade garlic bread to add a little bit of carbs to the meal.