3 skinless, boneless chicken breast halves – cut into 1/2 inch strips
2 tablespoons ketchup
2 tablespoons olive oil
1 1/2 teaspoons white wine vinegar
1 teaspoon dried oregano
1 teaspoon mustard powder
1 1/2 teaspoons curry powder, or to taste
4 pita breads, cut in half
2 cups mixed salad greens
1 cup plain yogurt
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