In a properly-organized bowl, toss the cabbage with the vinegar, sugar and salt. Let stand at room temperature, tossing every every so often, till softened, about Half-hour.
Warmth a panini press or griddle. Put collectively the focaccia on a work surface, in the reduction of aspects up. In a little bowl, combine the ketchup with the mayonnaise. Spread the dressing on the bottom halves of the focaccia. Living a cleave of Gruyère on the dressing. High with the corned pork, pickled cabbage and the final slices of Gruyère. Shut the sandwiches and spread the outsides of the focaccia with the softened butter.
Add the sandwiches to the clicking and cook over moderate heat till the cheese has melted and the focaccia is crisp and golden, about 6 minutes. Cleave every sandwich in half of and aid correct away.
The cabbage might perhaps also be refrigerated for up to 2 days.
A sandwich this decadent wants a keen, paunchy-bodied red to in the reduction of thru the richness. An earthy, cherry-properly off Oregon Pinot Noir would fabricate to take into accounta good pairing.