Preheat the oven to 400°F.
Make the maple-Dijon sauce: In a medium bowl, whisk together the broth, syrup, coconut aminos, mustard, garlic, vinegar, and tapioca flour. Set aside.
Cook the pork: In a small bowl, stir together the garlic powder, smoked paprika, rosemary, salt, and black pepper. Pat the pork tenderloin dry with paper towels and coat all sides with the spice mixture.
Heat the oil in a large cast-iron or ovenproof skillet over medium heat until shimmering. Add the pork and sear until browned and a crust forms, 2 to 3 minutes per side. Transfer to a plate and set aside.
Reduce the heat under the skillet to medium-low, add the sauce, and stir with a wooden spoon to release any browned bits from the bottom of the pan. Bring to a simmer and cook, stirring often, until the sauce thickens, about 3 minutes. Return the seared pork to the skillet and turn it with tongs to evenly coat with the sauce. Transfer to the oven.
Roast the pork until golden brown on the outside and it reaches an internal temperature of 140°F, 15 to 18 minutes.
Remove the pork from the skillet, cover loosely with aluminum foil, and rest on a cutting board for about 5 minutes, then cut it into ½-inch slices.
To serve, divide among four plates and drizzle with the pan sauce.
