Preheat your oven to 400°F (200°C) and place a heavy cast-iron skillet inside to heat.
Pat the ribeye steak completely dry with paper towels and season both sides with sea salt and black pepper.
Carefully remove the hot skillet from the oven, place it on the stovetop over high heat, and add the olive oil.
Sear the steak for 2 to 3 minutes on each side until a deep brown crust forms.
Transfer the skillet back into the oven and roast for 5 to 8 minutes, or until the internal temperature reaches 130°F for medium-rare.
Remove the steak from the skillet and let it rest on a cutting board for 10 minutes.
While the steak rests, halve the cherry tomatoes, finely dice the red onion, and cube the avocado.
In a bowl, toss the tomatoes, onion, and avocado with lime juice, extra virgin olive oil, and chopped cilantro.
Slice the rested ribeye against the grain and serve immediately alongside the zesty tomato avocado salad.