- Preheat your oven to 450F.
- Place the potatoes in a large pot and cover with cold water. Season the water with salt, cover the pot with a lid, and turn the stove on high heat. Once the water starts boiling, remove the lid and cook for 5-10 minutes, or until the potatoes are fork-tender. Drain the potatoes and pat them dry with a paper towel.
- While the potatoes are cooking, combine the melted butter with the garlic. Season with salt and pepper, set aside.
- Spray a large sheet pan with cooking spray.
- Arrange the potatoes, green beans, mushrooms, and onions on the sheet pan. Drizzle half of the garlic butter and gently toss so all the vegetables are coated with the butter. Season with salt and pepper.
- Roast the veggies for 20 minutes. They will be tender but not yet caramelized.
- Cut the Skirt Steak into smaller steaks, pat them dry and season with salt and pepper.
- Place the steaks over the vegetables and drizzle them with the remaining garlic butter.
- Turn the oven on broil and place the sheet pan in the oven. Broil for 4 minutes, then flip the steaks and broil for another 3-4 minutes for medium-rare.
- Remove the pan from the oven and let the steaks rest for 5-10 minutes before serving.