Use a paring knife to make diagonal cuts along the surface of the sausage.
Add one teaspoon of oil to a pan then begin to fry the sausages
After one minute, add the onions and sauté for another minute.
Once the onions begin to get tender, add the ketchup.
Add the chili flakes or cayenne pepper for some heat.
Add soy sauce
Continue to sauté until the onions are cooked and the sauce thickens.