Pre-heat your Griddler with the dials set for high-heat panini griddles.
Set out the bread slices on a cutting board or counter top.
Top with the meats and cheese.
Top the sandwiches with the chopped artichoke hearts.
Add the top slices of bread to form the sandwiches.
Brush the outsides of the bread slices with the oil.
Transfer to the Griddler and close the lid. Cook until the bread is golden brown and crunchy.
Remove and let cool slightly before opening to add mayonnaise to inside of top pieces of bread.
Slice and serve.
Notes
Do not put a lot of pressure on the griddle lid while cooking as it will cause the meats and cheese to escape. Try to keep the lid level so that the tops of the sandwiches cook evenly.