In a heavy large pot over medium-high heat, warm the oil. Add the onion, bell pepper, garlic, if using, and pepper flakes and sauté until the onion is translucent, about 8 minutes. Add the cumin and stir until fragrant, about 30 seconds. Add the turkey and sprinkle lightly with salt and black pepper. Cook until the turkey is no longer pink, breaking up the meat with a spoon, about 4 minutes. Add the beans and 2⁄3 cup (5 fl oz/160 ml) of their liquid to the pot along with the broth, green chiles, cream, and marjoram. Bring to a boil, stirring frequently. Reduce the heat and simmer to blend the flavors, stirring occasionally, about 15 minutes; thin with more bean liquid, if desired. Taste the chili and adjust the seasoning. Spoon into warmed bowls and sprinkle with cilantro. Serve right away with the toppings in bowls alongside.