In a medium-hot skillet, sear the Italian sausages in the olive oil until well browned on all sides, 2 to 3 minutes. Remove the sausages from the pan and set aside.
In the same skillet, sweat the onions over moderate heat for about 10 minutes, until tender and slightly caramelized.
Add the roasted peppers, ketchup, oregano, water, and sugar. Adjust se