Preheat your oven to 400°F (200°C). Slice the top off the head of garlic to expose the cloves, drizzle with 1 tablespoon of olive oil, and wrap in aluminum foil. Roast for 30-35 minutes until soft and caramelized. Allow to cool, then squeeze into a bowl and mash into a paste.

In a small bowl, combine the softened butter, mashed roasted garlic, chopped shallots, and finely chopped or ground porcini mushrooms. Season with sea salt and black pepper, mix well, and set aside.

Rub the porterhouse steaks with the remaining 2 tablespoons of olive oil. Generously season both sides with sea salt and black pepper. Rub the thyme leaves onto the steaks to coat evenly.

Heat a large cast-iron skillet over medium-high heat. Once hot, add the steaks and sear for about 4-5 minutes on each side to develop a nice crust.

Transfer the skillet to the preheated oven and cook for an additional 10-15 minutes, or until the steaks reach your desired level of doneness (135°F for medium-rare). Use a meat thermometer for accuracy.

While the steaks are cooking, lightly toast the Szechuan peppercorns in a dry skillet over medium heat until fragrant, about 2 minutes. Remove from heat and crush coarsely.

Once the steaks are done, remove from the oven and let them rest for about 5 minutes. Top each steak with a generous dollop of the porcini-shallot butter and a sprinkle of crushed Szechuan peppercorns. Garnish with chopped parsley.

Serve the steaks with your favorite sides and enjoy the rich flavors of roasted garlic, thyme, and the unique kick from the Szechuan peppercorns.