Remove the prime ribeye from the refrigerator at least 1 to 2 hours before cooking (depending on size). Pat it dry thoroughly with paper towels — dry surface = better sear.

Trim any excessively long pieces of fat if desired, but leave a good fat cap for flavor and moisture.

Combine kosher salt, black pepper, garlic powder, chopped rosemary and chopped thyme in a small bowl. Rub the seasoning evenly all over the roast, pressing to adhere. For best results, season liberally and let sit uncovered on a rack in the refrigerator for at least 4 hours or overnight (this step also aids in drying the surface). If refrigerating, bring back to room temperature for 1 hour before cooking.

Roasting & Searing

Preheat oven

Preheat oven to 275°F (135°C). Use a rack in a shallow roasting pan or a rimmed sheet pan with a wire rack so air can circulate beneath the roast.

Place the seasoned roast fat-side up on the rack. Insert a probe thermometer into the thickest part of the meat, avoiding bone. Roast in the oven until internal temperature reaches about 115°F (46°C) for rare, 120°F (49°C) for medium-rare; this will take roughly 1.5 to 2 hours for a 3 lb roast but monitor with the thermometer rather than time alone.

Sear for crust

While the roast approaches target temperature, heat a large heavy skillet (cast iron preferred) over high heat until very hot. Add the neutral high-smoke oil and swirl to coat. When oil is shimmering and just beginning to smoke, add the roast and sear each exposed surface — top, sides and edges — about 1 to 2 minutes per side until a deep brown crust forms. Use tongs to hold and sear the fat cap edge for even browning.

During the last minute of searing, add the dairy-free butter substitute (or unsalted butter if using), smashed garlic cloves, and thyme/rosemary sprigs to the pan. Tilt the pan carefully and baste the roast with the melted butter substitute and aromatics using a spoon, for 30–60 seconds to infuse flavor and finish the crust.

Resting & Carving

Transfer the roast to a cutting board and tent loosely with foil. Rest for 20 to 25 minutes (rest time roughly 5–10 minutes per pound) — internal temperature will rise another 5 to 10°F during resting, reaching perfect doneness (eg, roast taken out at 120°F will finish around 125–130°F for medium-rare).

After resting, optionally sprinkle a little coarse sea salt over the carved slices for added texture and flavor. Carve between the bones into ribeye steaks or slice across the grain into desired thickness (typically 1/2" to 1").

Garnish with chopped parsley if desired and serve immediately.