Cook the onions by heating 2 teaspoons of butter or olive oil in a large skillet over medium heat. Add the sliced onion and cook, stirring occasionally, for 15-20 minutes, or until slightly caramelized and golden brown. Season with sea salt and freshly cracked pepper, to taste. Side Note: If the onion starts to dry, add a little water to moisten. You can also add more olive oil if you prefer.
Remove the caramelized onions from the large skillet; set aside.
Cook the mushrooms by adding the last two teaspoons of butter or olive oil to the large skillet and heating over medium heat. Add the mushrooms once the pan is hot, and cook, stirring occasionally, for 3-4 minutes until tender.
To serve, place some garlic rice in a bowl, top with some warmed roasted tomatoes and grape tomatoes with asiago cheese, sliced steak, caramelized onions, and mushrooms. Serve and enjoy.