Sift together flour, salt , and baking powder. Keep aside.
Beat butter and sugar until it turns to creamy white, around for 4-5 minutes with the help of hand or stand mixer. Don't forget to scrape sides of the bowl during beating.
Add egg one by one and keep beating in between.
Beat continuously till it becomes light and fluffy.
Now add milk and vanilla essence in the batter and beat for few more minutes.
Add dry ingredients by folding with the help of a spatula.
Grease pan and dust with flour or place butter paper at the bottom of the pan.
Pour cake batter in a pan. I used a loaf pan.
Sprinkle the walnuts on top of the batter.
Bake in a pre heated oven at 350 F for 35-40 minutes. Check using toothpick.( If the toothpick inserted in the cake comes out clean then its done if there is batter sticking to the toothpick then it needs to be in the over a bit longer)