Pat the pork tenderloin dry and season generously with salt and pepper.
Heat olive oil in a large skillet over medium-high heat and sear the pork on all sides until golden brown, about 3 to 4 minutes per side. Remove pork and set aside.
In the same skillet, sauté minced garlic and chopped shallot for 1 to 2 minutes until fragrant.
Add chicken broth, scraping up any browned bits from the pan bottom, and simmer for 2 to 3 minutes.
Lower heat, stir in heavy cream, Dijon mustard, and thyme, and simmer gently for 3 to 4 minutes until sauce thickens slightly.
Return pork to skillet, spoon sauce over it, and simmer for 5 to 7 minutes until internal temperature reaches 145°F (63°C).
Slice pork tenderloin, pour mustard cream sauce over the top, garnish with fresh parsley, and serve immediately.