Most Easiest Marble Cake

This is the cake with which I started my journey of baking and though it's the most easy recipe I have come across till now, it's really valuable for me.
I name it the 'Most Easiest Marble Cake' to bake :D And for beginners, it's a good way to kick-off inshaAllah :) Till now, everyone who has eaten the cake has loved it. The soft texture of this cake is the most unique quality of it. Personally, I love to serve it warm but you can serve it according to your own preference.

Ingredients:
2eggs
1cup sugar
1cup plain flour
1/2cup oil
1/2cup milk
1tsp baking pwd
1tsp vanilla essence
3-5Tbsp cocoa pwd

Method:
STEP#1.Remind yourself you're gonna bake with love :)
STEP#2.Grease the baking pan and preheat the oven to 180C.
STEP#3.Sift flour and baking pwd in a bowl, and keep aside.
STEP#4.In another bowl beat eggs and sugar, until fluffy.
STEP#5.Slowly pour oil into the egg mixture, while keep beating at low speed. Beat at high speed for 1-2mins.
STEP#6.Fold in dry ingredients, vanilla essence and milk.
STEP#7.Pour the mixture into baking pan, keeping a little of the mixture in the bowl.
STEP#8.Mix cocoa pwd into the remaining mixture [add a couple of Tbsps of milk, if you feel that mixture has become too thick].
STEP#9.Pour the chocolate mixture over the vanilla one and SWIRL as you like
STEP#10.Bake for approx 35-45min. [Bake for How Long?]
STEP#11.Dust with icing sugar [or powdered sugar] or serve as it is.
warm cake+tea/coffee=love!