- 2 tablespoons unsalted butter, chilled and cut into pieces
- ¼ teaspoon black pepper
- 1/3 cup balsamic vinegar
- 1 tablespoon olive oil
- ½ teaspoon kosher salt
- 3 large shallots, thinly sliced into rings
- 1/3 cup low-sodium chicken broth
Heat the oil in a large skillet or saucepan over medium-low heat. Add the shallots and cook until softened, about 5 minutes. Add the broth and vinegar. Increase heat to medium, bring to a simmer, and cook for 2 minutes. Remove from heat. Add the butter to the skillet and swirl until melted. Seaso...