Preheat the oven to 450 degrees F. Line a large rimmed sheet pan with parchment paper. Spread the potatoes and garlic cloves out on the baking sheet and drizzle with olive oil. Then sprinkle generously with salt and pepper. Roast in the oven for 20 minutes.
Meanwhile, rub Dijon mustard over all sides of the steaks. Salt and pepper liberally on all sides. Then whisk the honey, balsamic vinegar, thyme, 1/2 teaspoon salt, and 1/4 teaspoon ground pepper together in a small bowl.
Once the potatoes have roasted for 20 minutes, push them to the sides of the pan and place the steaks on the sheet pan. Spread the green beans in between the steaks.
Place the sheet pan back on the center rack and turn the oven on broil. Broil the steaks for 5 minutes. Then flip the steaks over and drizzle the balsamic glaze over the top. Broil another 3-4 minutes, until the steaks are medium-rare and the glaze is bubbling. Remove from the oven and serve warm.