Learn how to easily make kek gula hangus or also known as kek sarang semut or bolu sarang semut. The cake has an amazing soft, bouncy with honeycomb/ants nest appearance when you cut the cake. Recipe can be made in the oven or air fryer.
What a weird name for a cake I know!! kek means cake, gula means sugar and hangus means burnt in Bahasa and Malay language. Sugar is caramelized and hence refers to the term “hangus”. In Malaysia and Singapore it is also known as Kek Sarang Semut (Ant’s Nest Cake). When you cut the cake vertically, you will see some honeycomb texture running up and down on the bottom half of the kek, almost like the one in Bika ambon. , but it doesn’t extend all the way to the top and it’s normal especially if the cake is really tall. When you cut the cake cross-section (horizontally), it resembles the ants nest, which is full of little holes (that makes me itch my skin when I look at it lol!).

cross-section of the cake reveals the ants holes appearance
Despite its “disgusting” look, you might think, this cake has an incredibly soft and bouncy texture that my two kids love a lot!
WHY YOU WILL LIKE THIS BOLU CARAMEL SARANG SEMUT
1. NO MIXER
You don’t need a stand mixer or a hand mixer. Just a whisk and some mixing bowls
2. AMAZING TEXTURE
I love the combination of tapioca starch and all-purpose flour that makes this cake soft yet bouncy and slightly chewy
3. CAN BE BAKED IN THE OVEN OR AIR FRYER
This is actually the first time I baked a cake in an air fryer and it turned out wonderful.
4. CAKE IS NOT OVERLY SWEET OR BITTER
Despite the scary dark brown color you see in kek gula hangus, the cake doesn’t taste burnt or worse bitter. The amount of sugar calls for in this recipe doesn’t make the cake overly sweet either.
INGREDIENTS
1. ALL-PURPOSE FLOUR
You can use either bleached or unbleached all-purpose flour
2. TAPIOCA STARCH
Tapioca starch adds an amazing bouncy texture to the cake
2. BAKING SODA
Baking soda helps to leaven and brown the cake in this recipe
3. BAKING POWDER
Baking powder is also used as a leavening agent in combination with baking soda
4. EGGS
Use any large eggs anywhere between 55-60 grams are good to go
5. CONDENSED MILK
Condensed milk adds that creamy sweetness to the cake
6. SUGAR
I use granulated sugar to do the caramelization
6. OIL
The oil keeps the cake really moist
HOW TO MAKE KUE SARANG SEMUT IN THE OVEN OR AIR FRYER
1. PREHEAT: Preheat oven at 350 F (180 C) or air fryer at 280 F (138 C). Line the pan with parchment paper or alternatively, grease the bottom of the pan with some oil or use non-stick cooking spray.
2. CARAMELIZE THE SUGAR:
Put the sugar on a saucepan over low-medium heat.
The sugar will slowly melt. Swirl the pan around as it helps to speed up the caramelization and to prevent the sugar from getting burnt. Control the heat. If the sugar burns, the cake will taste bitter. Don’t stir as the sugar will crystalize
Once the sugar has turned golden brown, slowly pour in the hot water. It will bubble vigorously. Be careful, this is hot sugar.
The sugar will crystalize a bit but don’t worry, keep stirring over medium heat
The sugar crystals will dissolve and then remove from the heat and let it cools down completely.
2. PREPARE CAKE BATTER
Whisk the dry ingredients and set aside. Use a hand whisk to beat the eggs and condensed milk until a bit foamy. Add the oil and combine again
Add 1/3 of the flour mixture alternating with the caramel sugar. Strain the batter to get rid of any lumps if necessary
Let the batter rest for a minimum of 30 minutes or up to 12 hours
3. BAKING IN THE AIR FRYER
Remove the inner basket of an air fryer. Place a metal trivet inside the air fryer box. This is how to set up looks like
Give the batter a stir and pour the cake batter into the prepared pan.
Set the pan on top of the trivet and bake for 15 minutes and then check for doneness. If the cake tester comes out still wet, bake in 5-minute increment until the cake is cooked through
4. BAKING IN THE OVEN
Give the batter a stir after resting and pour into the prepared pan. It should be only 3/4 full. Don’t fill up all the way as it will overflow. Place the cake on the lowest rack in the oven and bake for 30 minutes and then move to the middle rack and increase the temperature to 375 F (190 C) and bake for another 30 minutes or until a toothpick inserted into the cake comes out clean
Tips for success
1. Check to make sure your baking powder and baking soda are still fresh. The kek depends on these two to rise and to create that “sarang semut” texture
2. Watch carefully when you make the caramel. Do this over medium-low heat. If the sugar gets burnt, the cake will taste bitter
3. Make sure the caramel has cooled down completely
4. Strain the batter
5. Make sure you rest the batter for at least 30 minutes for the best result
6. Watch the oven temperature carefully. The ones I provided are just for reference. You can adjust it according to your own oven
TROUBLESHOOTING
The cake doesn’t have any honeycomb texture
1. Check the baking soda and baking powder to make sure they are still fresh
2. Your oven temperature may be too high OR too low. If the temperature is too high, the cake rises too quickly, it will deflate and turn into a dense cake. If the temperature is too low, the cake will not rise much and you end up with a dense layer and the cake will taste very eggy like custard
Do I need to add in baking soda just right before getting ready to bake the cake?
No, I have tried both, adding the baking soda while preparing the batter and after resting the batter and I didn’t see any difference in terms of the honeycomb texture
The kek gula hangus baked in a bundt pan has a slightly different pattern of honeycomb texture 🙂 Still pretty though!
The one baked in a regular round or square pan has a straight honeycomb texture.
DID YOU MAKE THIS KEK GULA HANGUS SARANG SEMUT RECIPE?
I love it when you guys snap a photo and tag to show me what you’ve made 🙂 Simply tag me @WhatToCookToday #WhatToCookToday on Instagram and I’ll be sure to stop by and take a peek for real!
Recipe is adapted from here with some modifications.
The recipe was last published in 2019 and after few more rounds of rigorous testings, I have updated the recipe and video on July 29, 2021 to rest the batter, update baking temperature and other tips for the best result.
Kek Gula Hangus/Kek Sarang Semut - Bolu Karamel Sarang Semut
Ingredients
For caramel:
- 250 gr sugar
- 250 ml hot water
Dry ingredients:
- 75 gr all-purpose flour
- 75 gr tapioca starch
- 1 ½ tsp baking soda
- 1 ½ tsp baking powder
- â…› tsp salt
Wet ingredients:
- 3 large eggs about 50 gr each (without shell)
- 100 ml condensed milk
- 100 gr cooking oil plus more for greasing the pan
Instructions
- For conventional oven, my oven (bottom heat): Preheat oven at 350 F (180 C). For convection oven (top and bottom heat), I suggest lowering temperature by 20 degrees
- For air fryer: preheat at 280 F (165 C) for 10 minutes
- Oil the bottom and sides of the pan. Line the pan with parchment paper at the bottom for easier release. If you use a bundt pan, oil and flour the pan. Tap out excess flour
Caramelize the sugar:
- Put the sugar on a saucepan over low-medium heat. The sugar will slowly melt. Swirl the pan around as it helps to speed up the caramelization and to prevent the sugar from getting burn. Control the heat. If the sugar burns, the cake will taste bitter. Don't stir as the sugar will crystalize
- Once the sugar has turned golden brown, slowly pour in the hot water. It will bubble vigorously. Be careful, this is hot sugar. The sugar will crystalize a bit but don't worry, keep stirring over medium heat until dissolved and then remove from the heat. Let it cools down completely.
Prepare the batter:
- Whisk the dry ingredients and set aside
- Use a hand whisk to beat the eggs and condensed milk until a bit foamy. Add the oil and whisk again to combine. Add 1/3 of the flour mixture alternating with the caramel sugar. Strain the batter to get rid of any lumps
- Cover and rest the batter for a minimum of 30 minutes and up to 12 hours. I have good results with both 30 minutes, 1 hour, and up to 12 hours. They are all soft and with good honeycomb texture.
Baking in an air fryer:
- Remove the inner basket of an air fryer. Place a metal trivet inside the air fryer box. Give the batter a really good stir and then pour the cake batter into the prepared pan. The pan should be only about 3/4 full. Don't fill up all the way or the cake will overflowSet the pan on top of the trivet and bake for 15 minutes and then check with a skewer. If it comes out still wet, bake in 5 minutes increment until a toothpick inserted comes out clean
Baking in the oven:
- Give the batter a really good stir after resting and pour into the prepared pan. The pan should be only about 3/4 full. Don't fill up all the way or the cake will overflow. Place the cake on the lowest rack in the oven and bake for 30 minutes and then move to middle rack and increase the temperature to 375 F (190 C) and bake for another 30 minutes or until a toothpick inserted into the cake comes out clean
Cool down the cake:
- Wait for 20 minutes and then remove the cake from the pan to let it cool down completely before slicing the cake
2 comments
Hi Marv, love your recipes they are authentic and so delicious! I had a problem with the Sarang Semut yesterday, it didn’t come out with the honeycomb like texture…. rather it came out looking more like Nian Gao on the inside.. Delicious nonetheless, but im just wondering what could have gone wrong? Any tips?
Hi Jeana, So sorry to hear of the problem. Hmm…is there any chance that the baking soda might be expired? You can test it out with about 1/2 tsp of baking soda and pour some hot water on it and it should sizzle vigorously almost immediately. If it doesn’t, the baking soda is no longer good.