1 cup balsamic vinegar
3/4 cup extra virgin olive oil
1 1/2 teaspoon salt, or more to taste
1/4 teaspoon freshly ground pepper, or more to taste
1 1/2 to 2 pounds mixed summer vegetables, such as summer squash, onion or peppers, cut for grilling
2 cups arugula leaves
1/4 cup toasted pine nuts
Whisk together the balsamic vinegar, olive oil, salt and pepper. Place the vegetables in a large, resealable bag and add the balsamic vinegar mixture. Let stand at least 30 minutes and up to 2 hours.
Prepare a grill to medium-high heat. Drain the vegetables and reserve the marinade. Place the vegetables directly onto the grate. Cook for 2 to 3 minutes per side, or to desired doneness. Remove the vegetables and allow them to cool slightly. When the vegetables are cool enough to handle, cut them into rough, bite-sized chunks and toss with the arugula and pine nuts. Add more marinade, salt and pepper to taste.