Amy's Creamy Black Bean Corn Salsa

1 (15 ounce) can black beans

drained and rinsed

1 ½ cups frozen corn

thawed

1 cup minced red bell pepper

¾ cup minced green bell pepper

½ cup minced red onion

1 tablespoon minced fresh parsley

½ cup sour cream

¼ cup mayonnaise

2 tablespoons red wine vinegar

1 teaspoon ground cumin

1 teaspoon chili powder

½ teaspoon salt

¼ teaspoon garlic powder

⅛ teaspoon ground black pepper