Chicken Souvlaki with Tzatziki Sauce

INGREDIENTS

• 1/4 cup olive oil
• 2 tablespoons lemon juice
• 2 cloves garlic, minced
• 1 teaspoon dried oregano
• 1/2 teaspoon salt
• 1 1/2 pounds skinless, boneless chicken breast halves - cut into bite-sized pieces
• Sauce:
• 1 (6 ounce) container plain Greek-style yogurt
• 1/2 cucumber - peeled, seeded, and grated
• 1 tablespoon olive oil
• 2 teaspoons white vinegar
• 1 clove garlic, minced
• 1 pinch salt
• 6 wooden skewers, or as needed