* ingredients :

°White granulated sugar, I was using 400g.
°220 grams of cake flour.
°80 grams of cocoa powder.
°1½ teaspoon baking powder.
°1½ teaspoons baking soda.
°1 teaspoon salt.
°I used 2 large eggs.
°A cup of milk/heavy cream. 
°Half a cup of vegetable oil
°A tablespoon of vanilla flavor.
°1 cup boiling water.
°Butter with Whipped Cheese Ingredients:
°120 grams of cream cheese.
°170 grams of soft butter.
°Half a tablespoon of vanilla flavor.
°500 grams of powdered sugar.
°Butter with Chocolate Cheese Ingredients:
°170 grams of butter.
°100 grams of cream cheese.
°About 2 cups of Hershey's cocoa powder.
°620 grams of powdered sugar.
°Half a cup of whole milk.
°2 tsp vanilla extract.

* Methods : 

Step 1:
To start, I set the oven temperature to 350 degrees Fahrenheit. I painted three medium-sized round cake pans using non-stick cooking spray.
Step 2:
Next, I set the pots aside after lightly sprinkling flour on them.
Step 3:
Next, I combined cake flour, cocoa powder, granulated white sugar, baking powder, baking soda, and kosher salt in a large mixing bowl, and mixed all of these ingredients together using an electric mixer. 
The fourth step:
Next I added whole milk, canola oil, 2 large eggs, and vanilla extract and whisked after each addition until well blended.
Fifth step:
Once mixed, I added the boiling water and whisked again for 40 seconds until I had a fluffy mixture.
Sixth step:
Next, I divided the mixture between the three pots and distributed them evenly, sorted them in the oven, and baked them for about 30 to 35 minutes, until a toothpick inserted in the center came out clean. 
Seventh step:
I removed the muffins from the oven once they were completely cooked and let them cool for at least 15 minutes after removing them on a wire rack.
Step 8:
To ensure even layers I always use a cake leveler, but you can also use a serrated knife.
Directions for making whipped buttercream directions:
Step 1:
For about 30 seconds, beat cream cheese with softened butter using an electric mixer on high pressure.
Step 2:
Until well mixed, I added 1/2 cup of powdered sugar at a time, making sure each 1/2 cup was added properly before moving on to the next 1/2 cup.
Step 3:
I added the vanilla extract and whisked for another 30 seconds on a heavy, then whisked for another minute until the mixture was smooth and fluffy.
Here is how to decorate buttercream:
Step 1:
First, I mixed the butter and cream cheese in a large mixing bowl with an electric mixer, then gradually mixed in ½ cup of the powdered sugar.
Step 2:
In a mixing bowl, combine cocoa powder, milk and vanilla extract.
Step 3:
Next, combine all ingredients in a mixing bowl and whisk until smooth.
The fourth step:
For a minute, or before thinning, beat at high speed.
Fifth step:
To ensure the perfect fit of the cake layers, I use a cake leveler to adjust the level of the cake, and place the bottom layer in a cake pan.
Sixth step:
I covered the bottom cake layer with three quarters of a cup of buttercream cheese. I repeated the procedure for the second single layer. Last but not least, I added the third layer on top and refrigerated for 15 minutes until the surface had set with the remaining buttercream and whipped cream cheese.
Seventh step:
Finally, I removed it from the refrigerator and gently added the chocolate sauce, buttercream cheese, and buttercream to the edges of the cake.

Enjoy !