Heat 2 teaspoons of the olive oil in a large saucepan set over medium heat. Add the onions and cook until translucent, about 5 minutes.

Add the cumin, oregano and garlic, and cook, stirring constantly, for 1 minute. Add the potatoes and salt, and stir to mix with the onions.

Push the potato mixture aside to form a clear spot in the center and pour in the remaining 1 teaspoon olive oil. Add the cornstarch, then stir into the potatoes, cooking for 1 minute.

Add the vegetable broth, corn, green chiles, and chipotle pepper, and stir to combine. Bring the mixture to a boil, then reduce the heat to a lively simmer and cook, uncovered, until the potatoes are tender, about 30 minutes.

In a medium-sized bowl, smash ½ cup of the white beans with the back of a fork. Add the smashed beans, along with the remaining whole beans and lime juice, to the stew. Simmer until the stew is thickened, about 10 minutes.

Stir in the cilantro, adjust seasoning to taste, and serve.