Preheat your sous vide(affiliate link) cooker to 135 degrees Fahrenheit.
Sprinkle the liquid smoke(affiliate link) and all the spices on top of one side of the top round roast. Do not include the butter! It is for searing the meat when it is done.
Carefully place the top round roast into a vacuum seal bag and seal it.
Once the sous vide(affiliate link) cooker reaches temperature, place the vacuum sealed bag with the top round roast into the water(affiliate link).
Cook for 15 hours.
Remove the bag from the sous vide(affiliate link) cooker.
Place the butter in a cast iron skillet(affiliate link) and let it melt. You want the butter melted and the skillet hot for the next step.
Carefully remove the top round roast from the bag. It might want to fall apart and you do not want that to happen.
Place the top round roast, seasoning side down in the cast iron skillet(affiliate link) and sear. This normally takes 2 to 3 minutes.
Turn the top round roast over and sear the other side.
Remove the top round roast, allow it to sit on a plate with a foil tent(affiliate link) for 10 minutes.
Cut and serve.
Note: I did use a semi-frozen top round roast. The time and temperature would be the same even if it was thawed completely. I also used the drippings in the bag to make a gravy once the searing of the meat was done. This is an optional step.