Pour oil into frying pan over medium-high heat. 

Use a knife or kitchen scissors to place small slits around the edge of the bologna in four spots. This will help the bologna not to roll up when cooking. 

Place the bologna in the heated oil.

Brown one side of the bologna, then flip using a spatula.

While browning the second side, place the cheese slice on top of the bologna. 

Spread your mayonnaise or mustard on one side of both pieces of bread. 

Place the bologna and cheese on top of the bread and top with the other slice. Make sure you keep the dry side of the bread to the outside. 

Enjoy!