3 tablespoons pine nuts or chopped slivered almonds
2 teaspoons extra-virgin olive oil
1 cup chopped onion(about 1 medium)
1/4 teaspoon salt, or to taste
4 cups broccoli florets
2 teaspoons balsamic vinegar
freshly ground pepper to taste
Toast nuts in a medium dry skillet over medium-low heat, stirring constantly, until lightly browned and fragrant, 2 to 3 minutes. Transfer to a small bowl to cool.
Add oil to the pan and heat over medium heat. Add the onion and salt, cook, stirring occasionally, adjusting heat as necessary, until soft and golden brown, 15-20 minutes.
Meanwhile, steam broccoli until just tender, 4 to 6 minutes. Transfer to a large bowl. Add the nuts, onion, vinegar and pepper; toss to coat. Serve immediately.