Pre-heat the sous vide water bath to 145°F.

Season all sides of the pork tenderloin with salt and freshly ground black pepper.

Combine the honey, olive oil, ginger, garlic, and lemon juice in a bowl and then pour it into a freezer zipper-sealable plastic bag. Add the pork tenderloin and massage it to coat it well with the marinade. Place the rosemary sprigs around the sides of the tenderloin. Remove as much of the air as possible from the bag by submerging the bag in the water up to the zipper seal (don’t let any water into the bag), and allowing the water to displace the air in the bag. Seal the bag and drop it into the water bath.

Cook the pork in the sous vide bath for at least 1½ hours, or as long as 4 hours.

Remove the pork tenderloin from the bag and dry it lightly with clean paper towels. Discard the rosemary sprigs, but reserve the cooking juices in the bag.

Pre-heat a sauté pan over medium-high heat. Add a little olive oil to the pan and sear the pork tenderloin on all sides until nicely browned. Transfer the tenderloin to a cutting board, cover with foil and let it rest for a few minutes.

Pour the reserved cooking juices into the sauté pan and bring to a simmer. Reduce the sauce for a few minutes until it has thickened. Add the chopped rosemary and season to taste. Slice the pork tenderloin and transfer the slices to a serving platter. Pour the sauce on top. Garnish with the fresh rosemary sprigs.