Step 1: Preheat the Oven
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Preheat your oven to 425°F (220°C) and wash the sweet potatoes thoroughly, ensuring they’re free from any dirt or debris.
Step 2: Prepare the Sweet Potatoes
Place each sweet potato on a cutting board and, using a sharp knife, make thin, evenly spaced slices along the length of the potato, being careful not to cut all the way through. Aim for slices about 1/8 inch apart.
Step 3: Infuse the Olive Oil
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In a small saucepan, heat olive oil over medium heat. Add minced garlic and chopped fresh rosemary to the pan, stirring constantly until the garlic is fragrant and just beginning to brown, about 1-2 minutes.
Step 4: Assemble the Dish
Place the sliced sweet potatoes in a cast-iron skillet or oven-safe dish. Brush the tops of the potatoes generously with the garlic and rosemary-infused olive oil mixture.
Step 5: Season and Bake
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Sprinkle the sweet potatoes with salt to taste. Transfer the skillet to the preheated oven and bake for 45-55 minutes, or until the sweet potatoes are tender and the edges are crispy.