Preheat oven to 450°F. Line a large rimmed baking sheet with nonstick foil. Place sweet potatoes on prepared baking sheet. Drizzle with 1 Tbsp. of the oil; toss gently to coat. Sprinkle with salt and pepper. Bake 30 minutes or until golden, stirring once.
Meanwhile, in a small skillet heat remaining 1 Tbsp. oil over medium heat. Add onion and garlic; cook 3 minutes, stirring occasionally. Stir in ketchup. Serve with fries.