Marinade the Pork: Combine the soy sauce, lime juice, maple syrup and sesame oil in a large resealable plastic bag. Add the prepared tenderloin. Close bag, pressing out the air. Flip a few times to coat the pork in the marinade. Place in the refrigerator and let marinade 2-8 hours. When ready to cook, remove tenderloin from marinade and discard marinade. Season lightly with salt and freshly ground pepper.
Cook the Pork: Preheat oven to 375°F. Heat oil in a large ovenproof skillet over medium-high heat. Sear tenderloin in hot oil, turning as needed, until browned on all sides, about 5 minutes. Transfer skillet to oven and roast until an instant-read thermometer inserted into the thickest part of tenderloin registers 135 - 140F, 10-15 minutes. Transfer pork to a cutting board and let rest at 5 minutes before slicing.
Prepare the sauce: While the pork is cooking, heat 1 Tbsp. oil in a large saucepan over medium heat. Cook shallot and garlic, stirring regularly, until softened, about 3 minutes. Add the curry paste and cook, stirring constantly, until paste is slightly darkened in colour and very fragrant, about 2 minutes. Add the coconut milk, lime zest, brown sugar and lime juice and stir to combine. Bring to a simmer and continue simmering until reduced and thickened.
To Serve: Slice pork in to 1/4-inch slices and arrange on a a deep serving platter. Spoon warm sauce overtop. Garnish with chopped cilantro and pumpkin seeds. Serve with rice, if desired.
Notes
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