Start by making the marinade in a bowl adding in the rosemary, thyme, garlic, lemon, salt and pepper and oil. The mixture should be salty because beef roasts need help with seasoning and it will make a delicious crust.
Cover roast in the marinade. This can be done the day before or 3 hours before cooking.
Cook roast for 20 minutes per pound at 350 degrees or until the inside reached 125 degrees. Let the roast sit out for 30 minutes before slicing.
Toast the Texas toast in the oven until golden brown.
Slice meat very thin and build the sandwiches with the provolone and horseradish on the Texas toast. Mayo and mustard are highly recommended.