Sift or whisk the flour, baking powder, and salt together in a small to medium-sized bowl.
2 cups (250 grams or 8.8 ounces) bleached all purpose flour, 1½ teaspoons baking powder, ¼ teaspoon salt
In a medium bowl if using a hand mixer or in the bowl of your stand mixer, mix the sugar and egg together on medium speed until it is light in color, 1 to 2 minutes.
¾ cup (150 grams or 5.3 ounces) granulated sugar, 1 large egg
Add the melted butter and ube extract and mix together for 1 minute.
8 tablespoons (113 grams or 4 ounces) unsalted butter, melted and slightly cooled, 2 teaspoons ube extract
Add the ube halaya and mix.
½ cup ube halaya (ube jam)
Add the dry ingredients and mix on low or stir in by hand just until they are fully incorporated.
Chill the cookie dough in the refrigerator for 30 to 60 minutes.
Meanwhile, preheat your oven to 350°F and ready a small bowl of confectioners' sugar and two cookie sheets lined with parchment paper or silicone mats.
½ cup confectioners' sugar, plus more if needed
Use a medium (#40) cookie scoop or two spoons to scoop balls of dough into the confectioners' sugar, and toss to coat thickly. Place on the baking sheets an inch to two apart.
Bake for 12 minutes in the middle of the oven. The cookies will be slightly firm to touch but the inside will look soft.
Let cool for about 5 minutes on the baking sheet before transferring them to a rack to cool completely.
Crinkle cookies can be stored for a week at room temperature.