For the cumin vinaigrette
2 teaspoons cumin seeds
1 teaspoon cracked black peppercorns
2 teaspoons dried oregano
1/2 cup plus 1 tablespoon olive oil
1 clove garlic, minced
2 tablespoons red wine vinegar
For the chickpea salad
2 15-ounce cans chickpeas, drained and rinsed
1/2 cup kalamata olives, pitted and sliced lengthwise
2 scallions, thinly sliced
1 tablespoon slivered mint leaves
1 ounce feta cheese, cubed