Preheat oven to 425°. Combine 1/2 teaspoon salt, black pepper, and 1/4 teaspoon ground cinnamon; rub over pork tenderloins. Heat a large ovenproof skillet over medium-high heat. Add olive oil. Add pork; sauté 4 minutes on each side. Remove pork, and reduce heat. Melt butter. Add apple slices and shallot to pan; sauté 1 minute. Stir in maple syrup, lemon juice, 1/4 teaspoon salt, and 1/4 teaspoon ground cinnamon; cook 4 minutes. Stir. Return pork to pan. Roast at 425° for 12 minutes or until a thermometer registers 145°. Remove pork from pan; let stand 5 minutes. Slice pork; serve with apples.