Amazingly soft and gooey crinkle cookies with a hint of ube or purple sweet potatoes are HUGE hit in our house. It’s hard to stay away from them.
PURPLE CRINKLE COOKIES
These amazingly soft ube or purple sweet potato crinkle cookies have become one of our family favorites every year. I like the crusty cookies on the outside but the inside is soooo soft, gooey and just melt in your mouth!! It has that hint of purple sweet potato that I love. Even if you don’t think you will like purple sweet potato or ube, you will not mind it in these cookies. For Real!
*Please note that I will mention both Ube or purple sweet potatoes in this post, but they are not the same thing. I tried the recipe with ube and two different types of purple sweet potatoes. The recipe can be made with any of the three*
You can read about the different purple sweet potatoes and ube in this purple sweet potato chiffon cake.
WHAT TO SUBSTITUTE FOR FRESH UBE OR PURPLE SWEET POTATO
If you can’t find fresh ube (I couldn’t), you can get the frozen grated ube and then steam it and mash. Another option is to use ube jam (ube halaya). This is usually has been sweetened, so you may need to cut down on the amount of sugar by half. I have yet to try it with ube jam.
WHY MY COOKIES TURN GREEN OR OTHER COLORS BUT PURPLE
I started getting comments from some of you who have tried this recipe and let me know that your cookies have turned green, or has green-blue speckles, some even brownish in color. Here’s the reason:
USE THE RIGHT PURPLE SWEET POTATO
I’ve made these crinkle cookies several times with ube, purple sweet potatoes (Stokes purple sweet potatoes), and Okinawan purple sweet potatoes and here’ what I found:
1. Ube dough
-The color of the dough remains very light purple after beating with butter and adding regular baking powder or aluminum-free baking powder. So, you can use either baking powder, which doesn’t cause the color change in this case.
-The color change to light brown after adding an egg. This is probably due to the purple and yellow from the yolk forming that light brown color.
2. Okinawan purple sweet potato dough
-The color of the dough remains purple after beating with butter and adding regular baking powder or aluminum-free baking powder. You can use either baking powder, which doesn’t cause the color change in this case.
-The color of the dough change to light brown too after adding an egg.
3. Purple sweet potato dough
The dough simply doesn’t change color even after adding an egg or after baking. This is the purple sweet potato I highly recommend to use in baking. They turn slightly darker after baking, but the purple color is still vibrant. In the U.S. here known as Stokes purple sweet potatoes.
IF YOU USE UBE OR OKINAWAN PURPLE SWEET POTATO
If you use ube or Okinawan purple sweet potato for this recipe, you will need to add food coloring. With ube, which the color of the purple is s much more subtle and weaker IMO, it’s hard for the natural color to shine through. SOOOO, I added food coloring for a consistent result. I know it’s not an ideal solution, considering some people, including myself, trying to stay away from artificial coloring as much I can, but if you want to consistently get nice purple color cookies, food coloring will come in handy. There are too many variables or unknown to me and I wish I’m a chemist to be able to tell you what could have gone wrong or didn’t happen!
I’ve read other recipes and wondering how they can get the color to be consistent and all of the recipes that I’ve seen, calls for use of ube extract, which will deepen the purple color of the cookies. I don’t have ube extract, and so I use mixture of blue and red to make the purple color.
IF YOU USE STOKES PURPLE SWEET POTATO (WITH BROWNISH PURPLE SKIN)
You don’t need additional food coloring. The natural coloring is deep enough and your cookies will not change color. They may turn slightly darker after baked, but the inside will have a nice purple color.
The cookies have that light taste of ube or purple sweet potatoes in it, which is really nice! Kids really are digging these cookies. I have to actually hide these cookies away from them LOL!
THE BEST WAY TO STORE COOKIES
1. STORE FRESHLY BAKED COOKIES: Let them cool down completely.Store them in an air-tight container (make sure it’s really air-tight) or zipper-lock bag with a piece of bread, no more than half size of the bread, at room temperature for 3-4 days. This will help to keep the cookies fresh longer.
For longer storage, I would suggest placing them in a freezer bag and freeze them. They can be kept up to 6 months. They can be re-crisped in the oven at 425 F for 4-5 minutes.
2. FREEZE COOKIE DOUGH: You can either roll the dough up into logs or I just roll them into little balls. I place the balls on a baking sheet and then place in the freezer for 30 minutes or so. They will firm up and then I transfer to freezer bag to save space. They can be thawed in the refrigerator overnight, then dip in confectioner sugar and then baked according to recipe.
These crinkle cookies are made with purple sweet potato (with brownish purple skin).
These crinkle cookies are made with ube.
*I decided to update this post based on inputs from people who have tried this recipe but does not get purple color cookies. This recipe has been tested with ube (purple yam), Okinawan purple sweet potatoes, and regular purple sweet potatoes (Stokes purple sweet potatoes). The method of making these cookies have also been streamlined for better result*
For baking/ kueh making: I highly encourage to weigh ingredients with a digital kitchen scale instead of using measuring cups as they are not very accurate especially when it comes to recipe that requires precision.GRAMS TO CUPS CONVERSION (UNSIFTED)
- 200 grams mashed purple sweet potato or ube or ube jam (ube halaya) - 1 cup, see notes
- 113 gr butter - 1 stick (1/2 cup), unsalted, softened
- 200 grams granulated sugar - 1 cup
- 1/2 tsp vanilla extract
- 1 large egg + 1 egg yolk - room temperature
- 120 grams confectioners’ sugar - 1 cup, for rolling & dusting cookies
Food coloring or ube extract (not needed if using Stokes purple sweet potatoes) - only use either one:
- 1 tsp ube extract
- Start with 4 drops blue food color + 6 drops of red food color
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 then steam for about 10-15 minutes or until easily mashable
- Get about 200 grams of purple sweet potatoes or ube to make cookies, you can eat the rest 🙂
Prepare cookie dough:
- Place the dry ingredients in a mixing bowl and whisk to mix. Set aside. Cream the softened butter and sugar until creamy, about 2 minutes over medium speed. Add room temperature eggs and vanilla extract. Stop halfway and scrape the side of the bowl. Add mashed potatoes or ube, food coloring or ube extract if you are using mashed ube, and cream them until smooth and creamy, about 1 minute
- Turn the speed to low and gradually add the flour mixture in 3 batches and let it mix until just combined. Don't overwork the dough. The dough will be sticky at this point
Shape the cookies:
- Preheat oven at 325 F. Scoop about 1 Tbsp of the cookie dough out. Roll it into a ball and place them on lined cookie sheet. Generously roll them in confectioners' sugar. Roll them several times 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 10 minutes for really soft cookies or 12 minutes if you want them crispier on the outside. They will still appear to be very soft when you pull them out from the oven. Let them cool on the baking sheet for 5 minutes then transfer to cooling rack. They will firm up a bit as they cool down. The inside is still so soft and super yum