*Using external thermometer for oven Is highly recommended , Oven temperatures can be inaccurate, using an external oven thermometer in your oven can be an easy fix for some of your cake baking problems. Using one will give you ACCURATE temperature readings.
*I baked all three cakes at the same time , you can bake one cake at a time, depending upon your size of the oven. Place the cake pan in the center rack of the oven ( instead of top or bottom - for even heat distribution).
*Use only a rubber spatula to cut and fold the flour mixture and soda to the condensed milk-butter mixture. Do not use a wire whisk or electrical hand mixer. Do not overmix.
*Avoid opening the oven door often in the initial minutes of baking ( cake will sink in the center).
*Make sure to grease the cake pan before pouring the batter , and after baking , let it cool down completely before removing the cakes from the pan.
*Sifting the all dry ingredients ( as mentioned above in the recipe) is important, it helps to remove any small lumps, and to distribute better. It also aerates the flour, and makes it easier to incorporate . Highly recommend to sift the mixture for at-least two to three times.
*Frosting - Some of the butter separates to the top ( you may notice a white layer) from the chocolates after melting or refrigeration , it is totally fine and normal.
*You can always bake the cake ahead of time and refrigerate it ( use a clear wrap as shown in the picture below to wrap them before refrigerating it). Bring the cake to room temperature, make the buttercream the next day, and frost the cake.
*Other Cake Recipes , Stepwise pictures given for all recipes in the blog,