Heat a chimney full of charcoal until they're white-hot.
Put 6 pcs of hot charcoal in a pile on the side of the kettle to make an indirect smoking setup.(Charcoal baskets are helpful for this).
Add a handful of wood chips to the coals and wait about 5-10 minutes to burn off some of the harsh first smoke. Vents are open about 1/4. Once the temperature reaches 275°F, you're ready to smoke.
Season the ribeye well and place as far away from the coals as possible to smoke it indirectly. Insert a thermometer to keep track of the temperature while it smokes.
Try to keep the kettle's temperature around 225°F and remove the steak once it reaches 100°F.Depending on the thickness of the steak and your BBQ's temperature this could take anywhere from 20 mins to 1 hour.
Once the steak reaches 100°F, remove it from the grill and place in a bowl or tray with the umami butter over top. Tent with aluminum foil.
Add the rest of the hot coals that you saved to one side of the grill and open all the vents. Get the grill ripping hot. (You can also use a hairdryer over the coals to accelerate the heating).
Brush the melted umami butter evenly over the ribeye. Sear the steak on both sides until nicely charred and the internal temperature of the thickest part of the steak reaches 120°F for medium-rare or 130°F for medium.
Let the steak rest in a warm place for 5 minutes and finish with cracked black pepper.Slice and serve while it's still warm. Enjoy!