Set the sous vide cooker to heat the water bath to 85ºC/185ºF.
Wash, peel and cu pumpkin into small cubes. Place in a food-safe vacuum bag and seal. (see tips above, if you do not have a vacuum sealer) Cook in water heated bath for 50 minutes.
When ready, remove cooked pumpkin from water bath and add to a blender, food processor, or use an immersion blender. Set aside to cool.
Make the custard:
Reduce water bath temperature to 80ºC/176ºF. Add the empty mason jars to warm with the water. This will help prevent cracks and breakage.
In a small saucepan, whisk together the cream and chai spice. You may choose to heat the cream, but it is not necessary. In this instance, I warmed the cream and spices.
In a medium bowl, combine all the remaining ingredients until well combined - I like to use an immersion blender. Slowly stream the cream/chai mixture into the pumpkin mixture, while mixing. Remove jars from water bath, dry the insides and evenly distribute among the four jars and seal, finger-tips-tight with the lids. (see tips above)
Submerge the jars in the heated water bath and cook for 60 minutes. Remove from the water bath when ready and place on a towel on the counter to cool at room temp. Transfer to an ice bath, then refrigerate for at least 4 hours, or overnight ideally.
Remove from the refrigerator and let sit for 10-15 minutes before bruleeing. Sprinkle with sugar and use a culinary torch to caramelize the sugar.