01 - Preheat the oven to 425°F. Arrange a rack in the center position.
02 - Toss the trimmed broccolini with olive oil, sea salt, black pepper, and lemon slices on a rimmed baking sheet. Spread in an even layer and roast for 18 to 20 minutes, flipping halfway through, until the stalks are tender-crisp and the edges are lightly charred. Remove from the oven and sprinkle with fresh lemon zest.
03 - Pat the steaks dry with paper towels. Season both sides generously with kosher salt and freshly ground black pepper.
04 - Heat a large cast-iron skillet over medium-high heat and add the olive oil. Once the oil is shimmering, lay the steaks in the pan and sear for 2 to 3 minutes per side until a deep golden-brown crust forms.
05 - Reduce the heat to medium. Add the butter, smashed garlic, rosemary sprigs, and thyme sprigs to the skillet. Tilt the pan slightly and use a spoon to continuously baste the steaks with the melted herb butter for 1 to 2 minutes, until the steaks reach your desired doneness (130°F internal temperature for medium-rare).
06 - Transfer the steaks to a warm plate and tent loosely with aluminum foil. Let rest for 5 minutes to allow the juices to redistribute.
07 - Serve each steak topped with pan juices alongside the roasted broccolini. Garnish with fresh lemon wedges.