Ube or Purple Sweet Potato Crinkle Cookies (with Egg or Eggless)
Prep Time: 30minutes
Cook Time: 13minutes
Chilling the dough: 4hours
Total Time: 4hours43minutes
Servings: 20cookies (depending on size)
Amazingly soft and gooey crinkle cookies with a hint of ube or purple sweet potatoes is a HUGE hit in our house. The recipe can be made with egg or without egg. All the tips you need to know to get the perfect crinkles and to prevent the powdered sugar from melting.
Mix ground flax seeds with water and let it sits for 10-15 minutes
Prepare ube or purple sweet potatoes:
If using fresh ube, Okinawan purple sweet potatoes, or Stokes purple sweet potatoes, peel the skin and then cut into large chunks and steam for about 15 minutes or until easily mash with fork. You can also microwave on high for 8-10 minutes or until soft.
If using frozen grated ube, thaw and pour off any excess liquid. Steam for about 10-15 minutes or until easily mashable. Pour off any excess liquid if any. Transfer to a food processor to blend until smooth consistency
Get 113 grams of ube or purple sweet potatoes to make cookies, you can keep the rest for other use
Place the dry ingredients in a mixing bowl and whisk to mix. Set aside. Use an electric mixer to cream the butter and sugar until creamy and pale on high speed, about 2 minutes. Add room temperature egg and egg yolk (for egg version) or soaked flax seeds (for eggless version). Cream again until just combined. Add ube or purple sweet potatoes, food coloring or ube extract and beat until jut combined
Add the flour mixture in 3 batches. You can switch to a spatula and let it mix until just combined. Don't overwork the dough. The dough will be very sticky at this point. As long as you don't see any more pockets of flour, you are done mixing
Chill the cookie dough:
Cover the mixing bowl and chill the dough in the fridge for at least 4 hours or in the freezer for about 2 hours. It is best if you can do it overnight. The longer you chill, the flavor will be more intense too and it's easier for you to work with the dough too
Shape the cookies:
Preheat oven at 350 F (180 C) for a conventional oven. You may want to lower the temperature by 20 degrees if you use a convection oven. When the oven is done preheating, scoop about 1 1/2 Tbsp (about 30 grams/scoop # 40) of the cookie dough out. With your lightly oiled palms, roll the dough into a round dough ball. The cookie dough is still sticky but easier to work with because it's cold. Place it on a lined cookie sheet, about 2 1/2-3 inches apart
Cover each one in granulated sugar first and then generously roll them in icing sugar. This step prevents the icing sugar from being absorbed by the dough and you won't get the crinkle effect. Roll them about 2-3 times in the icing sugar to make sure each ball is well-coated or the confectioners' sugar will not show much after baking
Pop them into the oven, 3rd rack from the top.Let them bake for 12 minutes for really soft cookies or 13-14 minutes if you want them crispier on the outside. The edge will set but the center is still soft when you pull them out from the oven. You don't want to overbake if you want a soft and chewy texture. Overbaking these cookies will give you a cakey texture. Let them cool on the baking sheet for 10 minutes then transfer to a cooling rack.
They taste better the next day onwards as I find that the texture is slightly chewier compared to when just freshly baked on day one IMHO
Let the cookies cool down completely and then keep in air-tight container. They can be kept at room temperature for about a week. If you want to keep the longer, freeze them
I notice that after chilled in the fridge or kept frozen, the cookies have an even "chewier" texture (if you enjoy that!). My kids like them that way :)
If you use mashed purple sweet potatoes instead of ube, the texture is going to be drier because purple sweet potatoes has less moisture. In this case, you want to add a about 1/2 teaspoons of milk or water as needed if the dough is dry. The cookie dough is supposed to be moist and sticky