Rinse pork tenderloin roast under cold running water and pat dry with paper towels.
Season roast with salt.
In a small bowl stir together, garlic powder, ginger, dry mustard, thyme, and pepper.
Rub seasoning mix over the entire roast massaging it in with your hands.
Heat a tablespoon of olive oil in a large skillet over medium heat.
Brown the seasoned pork roast in the skillet on all sides.
Transfer browned pork roast to a slow cooker.
Add chicken broth and soy sauce to the skillet to deglaze the skillet, scraping up any browned bits with a wooden spatula.
Bring chicken broth to a simmer then pour it over the browned pork roast in the slow cooker.
Add mushrooms and lemon juice to the slow cooker.
Cover and cook for 8-9 hours on low or 4-5 hours on high.
When ready to serve, remove roast from the slow cooker and tent with foil to keep warm.
Pour gravy into a saucepan.
Heat over medium high heat and bring the gravy to a simmer.
Combine ½ cup water and corn starch in a measuring cup to make a slurry.
Add the cornstarch slurry to the gravy and stir until gravy thickens. Remove from heat.
Shred pork roast with two forks.
To serve place a bed of mashed potatoes in a bowl. Top potatoes with shredded pork and gravy.
Garnish with freshly chopped parsley if desired.