Grease a bundt pan with oil and keep aside.
Take a bowl and add sugar, oil and initially only 3/4 cup of milk. (See note no. 5 below).
Whisk them very well.
Now add mashed sweet potatoes.
Give it a good mix and put on rest for 10 minutes.
After 10 minutes, place a sieve over the bowl and add flour, salt, baking powder, baking soda and spice mix.
Sift the ingredients into the bowl.
Give them a mix using cut and fold method. If the batter is too much thick, you can gradually add more (oats) milk to maintain the consistency.
Pour the batter into bundt pan.
Tap the pan twice to release air bubbles.
Bake in preheated oven @180°C for 35 to 40 minutes in the middle rack of the oven with both the rods on.
Take out of the oven and insert a toothpick in the cake. If toothpick comes out clean means cake is perfectly baked.
Let the cake cool down completely before inverting.