Preheat your oven to 200°C (390°F) and roast the pumpkin until it’s soft and caramelized, about 30 minutes. Let it cool completely before handling.
Place the cooled pumpkin into your blender, add a splash of orange juice, and sprinkle in the cinnamon. Blend until smooth and well combined, creating a creamy base.
Pour in the maple syrup and blend again until the mixture is uniformly sweetened and fragrant with spice.
Add the ice to the blender and pulse several times, blending until the mixture reaches a thick, icy slushie consistency. It should be cold and slightly granular but smooth overall.
Transfer the slushie mixture into a shallow dish, spreading it evenly with a spatula for quick and even freezing.
Freeze for at least 4 hours, stirring every 30 minutes to break up ice crystals and keep the texture smooth.
Once frozen to a firm, icy slush, scoop the pumpkin spice slushie into glasses. Garnish with whipped cream or a sprinkle of cinnamon for an extra festive touch.
Serve immediately and enjoy this cool, cozy fall treat that combines the flavors of pumpkin, spice, and citrus in a refreshing frozen form.