Heat about a tablespoon of grape seed or other oil along with a tablespoon of butter in a medium cast iron skillet on medium high heat. Start sauteeing onions, once they have soften add bell peppers. Salt. Add spices and stir. Cook until brown and nearly caramelized. Remove vegetables into a bowl. Next, brown the meat by placing a few (about 4-5) slices on the skillet and flipping over after a few seconds and salting slightly along the way. Don't crowd or allow the slices of meat to overlap. Keep removing browned meat, adding fresh slices and repeating. Once all the meat is cooked, add one tablespoon of butter to pan and dump meat, onions and peppers back into pan. Add cream cheese and allow to melt. Turn off stove, add shredded cheese and stir. Either toast up a sub and add filling, or place between two slices of sourdough and toast up on a panini press (adding more cheese if desired).