Mix cooked pumpkin and butter in a bowl until well combined. Add a pinch of salt and brown sugar, and mix thoroughly.

Sift cake flour, baking powder, and cornstarch into the mixture. Add black sesame seeds and mix until just combined.

Place the dough in a plastic bag, flatten it, and refrigerate for 30 minutes to 1 hour. Roll the dough to your desired thickness and cut into sticks.