Preheat oven to 325°F. Place four 6-ounce ramekins in a baking dish tall enough to hold water halfway up the sides (I use an 8x8 pan).

Heat the evaporated milk until it just starts to simmer. Do not boil.

In a heat-proof bowl, combine brown sugar, whole egg, egg yolks, pumpkin puree, vanilla, and spices. Whisk until smooth and fully combined.

Slowly pour the warm milk into the egg mixture, a little at a time, whisking constantly to temper the eggs.

Pour the custard through a fine-mesh strainer into a pitcher to remove any cooked bits, ensuring a smooth texture.

Divide the custard evenly among the ramekins. Leave a little space at the top (about ¼ inch) so the custard can expand slightly without spilling.

Optional: Use a kitchen torch to gently remove air bubbles from the surface, moving the flame in a sweeping motion.

Place the baking dish in the oven. Carefully pour hot water into the pan until it reaches halfway up the ramekins.

Bake for 40–45 minutes, until the edges are set but the centers still jiggle slightly when tapped. (Baking times may vary by oven and ramekin size.)

Remove the baking dish from the oven and set on a cooling rack. Let the custards sit in the water bath for 10 minutes to cool gradually.

Lift the ramekins out of the water bath and allow them to cool to room temperature. Refrigerate for at least 1 hour, or up to 2 days, before serving.