Aztec Salsa

INGREDIENTS

• 2 avocados - peeled, pitted, and chopped
• 1/4 cup red wine vinegar
• 1 (15 ounce) can black beans, rinsed and drained
• 1 (11 ounce) can Mexican-style corn
• 3 tomatoes, seeded and chopped
• 3 green onions, sliced
• 1 small red onion, chopped
• 1/4 cup olive oil, or as needed
• 1 (.7 ounce) package dry Italian-style salad dressing mix