Rinse and drain the 2 cans of black beans and 1 can of black-eyed peas in a colander under cold running water for 30 seconds to remove excess sodium and starch.
Transfer the rinsed beans and peas to a large mixing bowl.
Add 1 cup thawed frozen corn kernels to the bowl.
Finely dice 1 red bell pepper, ½ red onion, and 1 jalapeño pepper (with seeds removed) and add them to the bowl.
Chop ½ cup fresh cilantro and add it to the bowl.
In a separate small bowl, whisk together ⅓ cup olive oil and ¼ cup red wine vinegar until emulsified, about 15 seconds.
Add 1 tsp chili powder, ½ tsp ground cumin, ½ tsp garlic powder, ½ tsp salt, and ¼ tsp black pepper to the dressing and whisk again until fully combined.
Pour the dressing over the bean and vegetable mixture in the large bowl.
Gently toss all ingredients together with a large spoon until evenly coated, being careful not to mash the beans.
Cover the bowl with plastic wrap and refrigerate for at least 1 hour to allow flavors to meld, stirring once halfway through.
