Steps
1. Preheat the oven to 350°F (180°C).
2. Slice the croissant in half lengthwise without cutting through completely.
3. Spread butter on the inside of the croissant.
4. Sprinkle sugar evenly over the butter.
5. Close the croissant and place it on a baking sheet.
6. Bake in the preheated oven for 5-7 minutes until the croissant is golden and crispy.
7. Remove from the oven and let it cool slightly before serving.