Finely chop the onions. Core, seed, and chop or thinly slice the peppers. Cut the ham into small cubes.
Heat the oil in a medium-size casserole or a deep, large skillet over medium heat. Add the onions, reduce the heat to medium, and sauté until translucent, about 5 minutes.
Add the peppers, cover, and simmer gently until the peppers are somewhat tend