Preheat your oven to 400°F (200°C). Slice the top off the head of garlic to expose the cloves. Drizzle with a little olive oil and wrap in aluminum foil. Roast in the oven for about 30-35 minutes, or until the cloves are soft and golden. Allow to cool slightly, then squeeze the garlic cloves from their skins into a bowl and mash until smooth.

In a small bowl, mix the za'atar and toasted sesame seeds. Season the ribeye steaks generously with salt and black pepper on both sides. Press the za'atar and sesame mixture onto both sides of the steaks to create an even crust.

Heat olive oil in a large skillet over medium-high heat. Once hot, add the ribeye steaks and sear for about 4-5 minutes on each side for medium-rare, or until your desired doneness is reached. Transfer the steaks to a plate and let them rest.

In the same skillet, lower the heat to medium and add the mashed roasted garlic. Cook for 1 minute, then sprinkle in the flour and stir continuously for about 1-2 minutes until golden. Gradually whisk in the beef broth and soy sauce, scraping the bottom of the pan to incorporate all the flavorful bits. Bring to a simmer and cook for about 5 minutes until slightly thickened. Stir in the fresh thyme leaves and butter, then season with salt and pepper to taste.

Slice the rested ribeye steaks and arrange on plates. Drizzle with the velvety roasted garlic and thyme gravy. Garnish with fresh thyme sprigs if desired. Serve warm alongside your favorite sides.