Warm grapefruit and baby spinach salad

1. In a small bowl, whisk together the vinegar, olive oil, and pepper to make a vinaigrette.
2. Set aside.
3. In a large, nonreactive skillet over medium-high heat, melt the butter.
4. When the butter begins to foam, add the grapefruit, paprika, and salt.
5. Reducei the heat slightly and saute until the grapefruit is heated through, 2-3 min. add the spinach leaves and gently fold them together with the warm fruit just long enough to wilt the spinach, about 45 seconds.
6. Transfer the warm spinach-grapefruit mixture to a salad bowl and add the vinaigrette.
7. Tossi well and divide among 6 individual salad plates.