Take the New York strip steak out of the refrigerator at least one hour before cooking, and season with salt and black pepper.

Heat a non-stick skillet over medium-high heat for 2-3 minutes, then sear the steak for 2-3 minutes on each side.

Let the steak rest for 5 minutes before slicing it thinly against the grain.

In the same skillet, add sliced onions and sprinkle with salt. Cook until golden brown, about 10-15 minutes, then drizzle with balsamic glaze.

Slice the ciabatta loaf in half and toast on a skillet or broiler until golden and crispy, about 2-3 minutes.

Spread lemon herb aioli on the toasted ciabatta, layer with arugula, sliced steak, and caramelized onions.

Slice the sandwich in half and serve warm, showcasing the layers of flavor.