Heat the olive oil in a large skillet over medium-high heat. Add the onion, peppers, and jalapeƱo. Cook, stirring frequently, until the vegetables are softened and browned at the edges, 10-12 minutes. Stir in the garlic, oregano, and chili powder. Cook for 1-2 minutes. Stir in the black beans, tomatoes with juices, 2/3 cup water, and salt. Reduce the heat to medium and simmer until the mixture has thickened, about 20 minutes. Taste and add more salt, if needed.