This visually stunning salad combines zesty arugula, a flavorful Italian green, with the sweet piquance of blood oranges and the mellow, creamy richness of Gorgonzola cheese. The dressing is a deep red color and tends toward tartness; you can mellow its acidity as desired with a bit more olive oil or a teaspoon of honey.
Preheat the oven to 325 degrees F.
Spread the pine nuts on a cookie sheet and toast in the oven for 5 to 10 minutes until golden. You can also do this step in a skillet, but watch them very carefully — nuts burn easily.
Juice 2 of the blood oranges. You need 1/3 cup juice, so squeeze a third orange if necessary.
Make the vinaigrette by combining the vinegar, mustard, orange juice, salt, and oils in a jar and shaking vigorously to combine. Taste and adjust the tartness to your liking.
Peel the remaining blood oranges and slice crosswise into thin rounds. Cut each round in half.
Place the arugula in a large salad bowl and toss with just enough dressing to coat the leaves. Divide the greens between 4 to 6 chilled salad plates. Arrange the blood orange slices, pine nuts, and Gorgonzola on each salad. Drizzle with a bit more vinaigrette and serve immediately.