Place the ribeye in the freezer for approximately 20–30 minutes before slicing. This makes it easier to cut into very thin strips.
Heat half the butter in a large frying pan. Add the onions and a pinch of salt and cook for approximately 5 minutes.
Add the capsicum and continue cooking for another 12–15 minutes, until the onions are caramelised and the capsicum is soft.
Combine the mayonnaise, roasted garlic and salt if using.
Split the sandwich rolls and toast the cut sides with the remaining butter.
Heat the olive oil in a large frying pan over high heat. Cook the ribeye quickly in batches until browned.
Season properly with salt and cracked black pepper, then add the Worcestershire sauce.
Return the caramelised onions and capsicum to the pan and mix through the steak.
Divide the filling into four portions. Cover each portion with provolone and allow it to melt.
Spread roasted garlic mayonnaise inside the toasted rolls, if desired.
Fill each roll generously with steak, caramelised onions, capsicum and melted provolone.
