Preheat oven to 400F.
Mix sweet potatoes with olive oil, salt, and pepper to coat. Spread in an even layer on a prepared baking sheet. Bake for about 45 minutes or until fork-tender. Flip halfway through to ensure even baking. Baking time can vary quite a bit, depending on variety of potato, chunk size, and climate, so start checking before 45 minutes.
While the sweet potatoes are baking, add the cowpeas, green onions, red pepper, corn, and cilantro to a large bowl. Set aside.
Add all the dressing ingredients to a medium bowl and whisk to combine. Set aside.
Once the sweet potatoes are done, add them to the large bowl, add the dressing, and toss to combine. Taste for flavour balance, tweak if needed, and serve. The salad is great warm, but is also good at room temperature.
Servings 4