For best results, salt the roast liberally the night before cooking and leave it, loosely covered, in the refrigerator. This step is technically optional, but it is also strongly recommended.
Preheat your oven to 200°F (93°C).
If you salted the roast the previous night, apply pepper as well. If not, apply salt and pepper
Heat a cast-iron skillet or a griddle on the stove over high heat. When the pan is quite hot—400–475°F (204–246°C) (use an Infrared Thermometer)—add a little high smoke point oil to the pan and sear the roast all over until beautifully browned.
Remove the roast from the pan and place it on a rack set into a cookie sheet.
Insert an RFX MEAT into the center of the roast and place the roast in the oven to cook. Set the high-temp alarm on the ThermoWorks app for 130°F (54°C).
When the alarm sounds (it will probably be 90 minutes or more), test the doneness of the roast with your Thermapen ONE. If that test verifies doneness, remove the roast from the oven and let it cool.
Once the roast is nearly room temperature, put it in the fridge overnight. Make sure it cools quickly enough.
Slice it to whatever thickness you like for your sandwich, pile it on the bread, and go to town. Enjoy!