Rub olive oil all over the steaks and then generously season them on both sides with salt, pepper and garlic powder
Air Fryer: Preheat the air fryer for 5 minutes at 400 degrees Fahrenheit. Place the steaks in the air fryer and cook for 5 minutes and then flip and cook for another 5 minutes. Stovetop: Heat a pan on high heat, once hot (but not smoking) add the steak and cook for 3 minutes before flipping and cooking for an additional 3 minutes. Let the steaks sit on a cutting board for 5 minutes before slicing into strips.
While steaks are cooking prepare the onions. Melt butter in a pan on medium high heat. Add in the onions and sprinkle with salt. Cook for 5 minutes until the onions begin to soften and then add in the honey and balsamic and cook for 8-10 minutes until the liquid has evaporated and the onions are soft and coated in the honey balsamic sauce.
In a small bowl stir together the mayonnaise, garlic and chives.
Preheat the oven to 350 degrees. Slice the ciabatta rolls, place them on a baking sheet and butter one side of each and place the thin slices of brie on the other half. Place the tray in the oven and leave for 4-5 minutes until the cheese begins to soften (but not completely melt) and the bread becomes toasted
Assemble the sandwiches by spreading the mayonnaise sauce on the buttered half, followed by the sliced tomato and arugula. On the half with the brie cheese add the steak and a big spoonful of the onions. Combine the two halves and enjoy.