Place squash halves in a shallow baking pan with about 1 inch of water.
Bake squash in the preheated oven until soft, about 1 hour.
Scrape flesh of squash from the rind using a fork and place in a large serving bowl.
Heat 1 tablespoon olive oil in a large skillet over medium heat. Cook and stir the black beans, tomatoes, bell pepper, and garlic in the hot oil until the vegetables are soft and the liquid has reduced, about 10 minutes; pour into the bowl with the squash; toss to combine. Add 1 tablespoon olive oil, the vinegar, and cilantro and toss again. Season with salt and pepper to serve.