Okinawan sweet potato haupia pie is a popular dessert from Hawai’i. My recipe features a macadamia nut cookie crust, purple sweet potato filling, and an easy coconut topping.
Okinawan sweet potato haupia pie is a mouthful to say… but it’s a very delicious mouthful. In fact, I love this Hawaiian dessert so much, I already have a recipe for it. The crust in this version is a little more complicated than my previous version, so this is for the next level purple pie lovers. My recipe is an adaptation of a very old recipe I received from a Japanese American friend whose family lived in Hawai’i. Ironically, my Japanese family also immigrated to Hawai’i before coming mainland, but no one in my family ever baked pie. Like, ever. And you know what? I’m actually really bad at baking pies too. Is it genetic?! A pie baking gene I have somehow missed out on? All that to say, I am not an expert pie baker, but I can still successfully pull off this recipe, which means you can too!
You can make this pie in a 9 inch pie tin OR a 9×13″ rectangular baking dish. If you make the 9×13″, you’ll need to double the filling and haupia portions.
What is Okinawan Sweet Potato?
Okinawan sweet potato is a sweet potato from the morning glory family with light brown skin and bright purple flesh. When cooked, the flesh becomes a striking dark violet. As the name implies, this sweet potato is commonly grown in Okinawa, Japan. Studies on this nutrient rich sweet potato have connected it with the famously long life span of Okinawans.
Okinawan sweet potatoes are also very popular in Hawai’i! This sweet potato pie with haupia topping is a very beloved dessert among my friends who live Hawai’i.
Purple Sweet Potato Substitutions?
You may be able to find Okinawan sweet potatoes in Asian markets, especially Japanese and Korean, in the mainland US. In my experience, they are not always available and/or can be extremely expensive. Just recently in Seattle some were selling for over $5 a pound!
If you don’t have access to Okinawan sweet potatoes, you may be able to find Molokai sweet potatoes as a substitute. They are sometimes sold as “purple yams,” and have dark purple skin and flesh. They cook up the same as Okinawan ones and have a similar color and flavor profile. I find the Molokai potatoes to have more of a yam-like flavor with floral notes, whereas Okinawan ones have a sweet flavor like pure cane sugar. A strain of Hawaiian purple sweet potatoes have also been patented by a farm in North Carolina and sell them as “Stokes” sweet potatoes, if you can find those.
How to Cook Okinawan Sweet Potato
You can cook Okinawan sweet potatoes the same way you cook other sweet potatoes or yams. To use the flesh in dessert recipes like this one, I like to microwave my potatoes until soft, peel the skin, and mash the insides. However, you could also bake them in the oven or grill them. I’ve not tried boiling them, but I suppose that would work too!
What is Haupia?
Haupia is a traditional Hawaiian dessert made from coconut milk. Similar to jello, you heat and mix the ingredients on the stove before pouring into a mold and letting it set in the fridge. In this case, we are pouring the haupia as the top layer in our pie. Check out this post for a classic haupia recipe, no pie involved!
Making Macadamia Nut Pie Crust
Honestly, the macadamia nut crust has just as much main character energy as the purple sweet potatoes in this recipe. Have you had Honolulu Cookie Company or Big Island Candy cookies? It’s like taking a bite of those with every slice!
Now, I am notoriously bad at pie crusts. It is my greatest baking weakness. So let me tell you that you CAN make this pie crust! If you can make cookies, you can do this.
Just like with cookies, you’ll cream room temperature butter with sugar. Then add eggs, flour, and macadamia nuts. That’s it! Press into your pie tin and bake. You’re going to slightly underbake the cookie dough, since it will continue baking after you’ve got the sweet potato filling in.
More Hawaiian Dessert Recipes
If you’re looking for more Hawaiian desserts you can make at home, check these out:
- Classic Hawaiian Butter Mochi
- Haupia – Hawaiian Coconut Pudding
- Chocolate Haupia Pie
- Easy Homemade Mochi (Chi Chi Dango)
- Almond Jello (Almond Float)
Okinawan Sweet Potato Haupia Pie
Equipment
- 1 9" round pie tin
Ingredients
For Macadamia Nut Crust
- 8 tbsp softened, unsalted butter
- 1/4 cup granulated sugar
- 1/2 tsp salt
- 1 egg
- 1 1/2 cups all purpose flour
- 1/2 cup chopped macadamia nuts optional
For Sweet Potato Filling
- 1 cup purple sweet potato puree 180g, from about 1-2 sweet potatoes
- 6 tbsp sugar
- 1 egg
- 1/4 cup heavy cream or half and half
- 4 tbsp melted butter
- 1 tsp vanilla extract
For Haupia
- 1 12 oz can coconut milk
- 3 tbsp sugar
- 3 tbsp cornstarch
- 1/4 cup water
Instructions
Make the Crust
- Preheat oven to 350 degrees F.
- With an electric mixer, cream butter, sugar, and salt until fluffy.
- Add egg and mix until homogenous. Then add flour and macadamia nuts and mix until just combined.
- Press dough into a greased 9" pie tin, making sure the dough goes all the way up the sides of the tin.
- Bake in the oven for 12 minutes while you prepare the sweet potato filling.
Purple Sweet Potato Filling
- Cook your sweet potatoes to make a puree: you can do this in the microwave, in the oven, or by boiling – however you would normally cook a potato. I typically use the microwave: poke holes in your sweet potatoes with a fork, cover, and microwave for 6-7 minutes or until you can very easily pierce through the sweet potato. Peel the skin off the potatoes and mash the insides very well. You can do this a few days ahead of time and save the puree in the fridge.
- Take one cup of sweet potato puree and mix with the sugar, egg, heavy cream, melted butter, and vanilla extract.
- Spread the filling over the crust.
- Bake until set – about 20 minutes, or until a toothpick poked in the center comes out clean. (Note that the butter may leak from your crust, causing the filling to look liquidy when it is actually cooked, so use a toothpick as your gauge.) Set your pie aside to cool while you cook the haupia.
For the Haupia
- Mix sugar, cornstarch, and water in a separate bowl to make a slurry.
- Pour can of coconut milk in a pot and heat on stovetop.
- When the coconut milk is just starting to bubble, pour in your cornstarch slurry very slowly while continuously whisking the hot coconut milk in the pot. It's important to keep stirring to avoid lumps.
- Cook the haupia, continuously whisking, until the mixture has thickened to a pudding like consistency but is still pourable; this should only take a couple minutes. Do not let the mixture come to a full boil.
- Take the haupia off the heat. Then, very gently spread over the purple sweet potato filling.
- Place the pie into the fridge to let the haupia layer set. I like to leave it uncovered in the fridge until the top has become dry to the touch, then I cover with plastic wrap.
- When the pie has fully cooled and the haupia is set (at least two hours), you can cut it into squares to serve.
Video
Notes
- If you can’t find Okinawan sweet potato or they’re too expensive, you can use Molokai sweet potato, which is purple on the outside and inside. The Stokes sweet potatoes brand are an example of a Molokai sweet potato.
- You can also make this recipe in a 8×8″ square baking dish using half the crust recipe.