Preheat the oven to 350°F (175°C).

In a large mixing bowl, combine pumpkin puree, brown sugar, eggs, milk, cinnamon, nutmeg, and vanilla extract. Whisk until smooth and uniform.

Grease a baking dish or individual ramekins. Pour the custard mixture into the prepared dish, filling it about three-quarters full.

Bake for 30–35 minutes or until set with a slight jiggle in the center.

Allow the custard to cool at room temperature for 10-15 minutes.

Serve warm or chilled, topped with whipped cream and toasted pumpkin seeds.