Steak Sandwich Recipe with Caramelized Onions and Bacon

0 Set the butter out to soften. 
6 Preheat the oven to 350°F. Cut the end of each garlic bulb off and coat in olive oil and sprinkle with salt. Wrap the bulbs in foil and place in the oven for 1 hour. 
7 Once cool to the touch, squish each clove of garlic out into a bowl with the softened butter, and macerate the garlic with a fork, combining it with the butter. Set aside to use for later.
1 While the garlic roasts, place 4 tablespoons of oil in a preheated cast iron pan, turn the heat to low and place the thinly sliced onions in the pan. Slowly cook the onions, stirring occasionally, until they're a golden color (about 45 minutes).
2 When the onions have about 25 minutes left, season the steak with the garlic powder, onion powder, salt, cumin, paprika, and black pepper.
3 Heat 2 tablespoons of olive oil in another skillet over high heat. Once hot, add the steak and sear for 4-5 minutes. Flip the steak, and continue cooking until a meat thermometer inserted into the thickest part of the steak reads 140°F. Remove the steak from the pan and let it rest until it comes to 145°F. Then, slice it against the grain.
4 Assemble the sandwiches by slathering the garlic butter on each slice of bread. Sprinkle the cheese on top of the buttered bread, and broil until the cheese is melted.
5 Layer the steak, caramelized onions, and bacon one one side of the bread and the arugula, pepperoncinis, and sliced avocado on the other side of the bread. Place the two halves together, and enjoy!