¼ cup white balsamic vinegar, (regular is fine, too)
kosher salt and pepper to taste
1 cup extra-virgin olive oil
¼ cup chopped scallions, green part only, cut on the diagonal (optional — I don’t add the scallions because I like to keep a jar of this in my fridge for a long time)
In a small saucepan, bring the orange juice to a simmer over medium-low heat and cook until it has reduced to ½ cup, about 10 minutes. Remove from heat, transfer to a medium-sized bowl and allow to cool to room temperature. Once cool, whisk in the vinegar and salt and pepper to taste. Slowly whisk in the olive oil. Transfer to a jar and store in refrigerator until ready to serve. Bring to room temperature before using.