Orange and Pineapple Beef

INGREDIENTS

• Kosher salt and freshly ground black pepper
• 1 (4 to 5-pound) beef tenderloin, trimmed
• 1/2 teaspoon kosher salt, plus extra for seasoning
• Vegetable oil cooking spray
• 1/4 cup fresh lemon juice (from 1 large lemon)
• 3 cloves garlic, coarsely chopped
• Garnish: orange slices, optional
• 1/4 cup low-sodium soy sauce
• 1 tablespoon arrowroot
• 1 cup orange juice
• 1 (1-inch) piece fresh ginger, peeled and coarsely chopped
• 1 (20-ounce) can pineapple chunks in heavy syrup
• 3 tablespoons vegetable oil
• 3 tablespoons sugar