Whisk together cream, pumpkin, dark brown sugar and pumpkin pie spice in a medium size bowl (preferably, with a pouring spout). Set aside.
Remove from heat. Carefully add cream/pumpkin mixture (mixture may bubble up and steam). Whisk until combined. If caramel mixture does not completely dissolve, return pot to heat and stir for a minute or two until dissolved.
Pour custard through a fine-mesh sieve back into the egg yolk bowl. Divide custard among ramekins or pots in the pan. Pour hot water into pan the ramekins are in to reach about half way up the sides. Bake, uncovered, until custards are set around edges, but still tremble slightly in centers, about 35-45 minutes.
See Café Tips above in post for further instructions and more detailed tips.
This recipe will serve 6-8, depending on the size of your bowls or ramekins.