In a medium saucepan, combine the heavy cream, whole milk, and granulated sugar over low heat. Stir occasionally until the sugar dissolves and the mixture is warm, ensuring that it does not boil.

In a separate bowl, whisk together the pumpkin puree, vanilla extract, cinnamon, nutmeg, and salt.

Carefully whisk the warm cream mixture into the pumpkin mixture until well combined.

Transfer the entire mixture back into the saucepan and heat gently again, stirring constantly for a few minutes until it thickens slightly.

Remove from heat and let the mixture cool to room temperature.

Refrigerate the mixture for about 2 hours to chill completely.

Pour the chilled mixture into your ice cream maker and churn according to the manufacturer's instructions, typically for about 20-30 minutes.

Once it reaches a soft-serve consistency, you can serve it immediately or transfer it to an airtight container and freeze for an additional couple of hours for firmer ice cream.