Prepare a big deep vessel or kadhai for baking the cake without oven by adding 2 cups salt to it. Place a small hollow ring to create a gap. Cover the vessel or kadhai with a lid and heat it on high for 15 minutes.
Prepare the dry ingredients by sieving the all purpose flour, baking powder, baking soda and salt through a sieve. Mix it with a fork. Keep it aside.
Take a big bowl and add fresh cream and sugar to it. Whisk it together using a whisker until well combined.
Now add milk powder, custard powder and oil to it. Mix well.
Add half cup warm milk and half of the dry ingredient mixture to it. Mix well.
Add the remaining half cup warm milk and remaining dry ingredients and mix well.
Add vanilla essence or extract to it. Mix well.
Add tutti frutti to it and mix well. The batter consistency should be little thick but not too thick. (Add more milk, if required)
Grease the baking pan (preferably loaf baking pan 9x4 inch) with butter.
Transfer the batter to the baking pan, spread it evenly. Tap it on the counter to remove air bubbles.
Place the baking pan in the pre heated vessel or kadhai. Cover the lid and let it cook on medium - high heat for 45-50 minutes (Check it after 45 minutes).
Insert a toothpick in the cake, if it comes out clean, turn off the heat and remove the cake.
Cut the cake into equal 10 slices. Bon appetite!