Caramel Cake [Kek Sarang Semut] AGAIN

I made this before with a slightly different recipe. Kek Sarang Semut (ant's nest cake) is unique for its 'hole-y' texture likened to an ant's nest. It is slightly spongy and it has very soft crumbs. 

Recently, I decided to have a go at the recipe again after having a slice at my cousin's house during one of my Eid visits. It's much similar to the previous one except that it has lesser condensed milk (just 2 tablespoons instead of 1 cup) and this one uses Self-raising flour instead.

You'll need:
8 x 6 x 3 pan lined and greased

Step 1- Prepare caramel.
1 cup of castor sugar
1 cup of hot water
2 tablespoons of butter.

Melt the sugar in a heavy based pan till it changes colour. Let it go to dark brown (this will determine the colour of your cake), and slowly pour the hot water. Be very careful because it may splatter and you may get burnt. I had my oven mitts on. Stir as you add the hot water. Let the mixture boil as it dissolves all the caramel. Off the fire and add in the butter, allow to melt. Set aside and allow it cool slightly.

Step 2 - Batter
4 eggs
2 tablespoons sweetened condensed milk
1/2 teaspoons vanilla essence
1 cup Self-raising flour
2 teaspoon soda bicarbonate
(sieve flour and soda bicarbonate together)

Whisk the eggs till frothy and add condensed milk as well as vanilla essence. Mix well.
Slowly fold in the sieved flour+soda bicarbonate into the egg mix.
Lastly pour in the caramel and mix well.
Cover batter with plastic wrap and let it sit for 2-3 hrs.

Preheat oven to 170 deg celsius.
Pour batter into prepared tin and bake for about 1 hour.

Let cool before cutting cake.