A shooter's sandwich.
I used a red onion instead of shallots and used portabella mushrooms. I also added a layer of provolone cheese. I sautéed everything in Olive Oil instead of butter.
It only took 5 hours and 20 minutes to make! Super easy actually - 20 minutes to cook the steak and veggies. 5 hours of it resting under a bunch of weights (that's the most my weights have been used in 3 years).
I was scared to eat it after sitting out for 5 hours so I made my wife take the first bite. We finished off half of it after that.