In a bowl, mix the steak with seasonings, minced garlic and lime juice. Set it aside.
While the steak marinates, set the frying pan to medium-low heat and add 1 tablespoon of oil. Once hot, add sliced onions and cook until soft (about 5-6 minutes).
When the onions are cooked, remove them from the pan and increase the heat to medium-high heat.
Add more oil, then the steak and cook for 2-3 minutes per side until golden brown.
Cut the steak (against the grain) into thin strips.
Assemble the sandwich by cutting the loaves into the portion you desire. Add mayonnaise, steak strips, caramelized onions and potato sticks.
Press your sandwich in a panini press if you have one. Otherwise, brush the outside of the bread with butter then press it into a skillet for a minute or so per side.
If desired, add sliced tomatoes and lettuce and serve.
¡Buen provecho from The Happy Wookiee!