Start by grabbing a medium-sized bowl. Whisk together the all-purpose flour, baking powder, ground cinnamon, and salt. Mixing these dry ingredients first ensures that the baking powder and cinnamon are evenly distributed throughout the dough, which means every cookie will be perfectly spiced and will rise beautifully.

In a separate, larger bowl, it's time to mix the wet ingredients. Combine the granulated sugar, brown sugar, and vegetable oil. Beat them together until they are well-blended. Next, add the eggs one at a time, followed by the vanilla extract, mixing until the mixture is smooth. Gradually add your pre-mixed dry ingredients to this wet mixture, stirring gently until a soft, slightly sticky dough forms.

This is the most critical step for getting those signature crinkles! Transfer the dough to a bowl, cover it tightly with plastic wrap, and place it in the refrigerator to chill for at least two hours. This chilling period allows the flavors to deepen and solidifies the dough, preventing the cookies from spreading too much in the oven.

Once the dough is properly chilled, preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. Use a small cookie scoop or your hands to form the dough into 1-inch balls. Pour some powdered sugar into a shallow bowl and roll each dough ball generously in the sugar until it's completely coated.

Arrange the sugar-coated dough balls on your prepared baking sheet, leaving about two inches of space between each one to allow for spreading. Bake for 10 to 12 minutes. The cookies are done when the edges are set and the centers are still soft. They will continue to firm up as they cool on the baking sheet.