Red Velvet Cake with Powdered Milk Filling

Ingredients
For the dough:
2 cups of wheat flour
1 ½ cups of sugar
1 cup of vegetable oil
1 cup of buttermilk (or milk + 1 tablespoon of vinegar)
2 eggs
2 tablespoons of cocoa powder
1 tablespoon of vanilla extract
1 tablespoon of red food coloring (gel or liquid)
1 tablespoon of baking powder
1 teaspoon of baking soda
1 teaspoon of salt

For the powdered milk filling:
1 can of condensed milk
1 cup of powdered milk
100g of butter (at room temperature)
1 teaspoon of vanilla extract
1/2 cup of cream

For the cream cheese frosting (optional):
200g of cream cheese
100g of butter
2 cups of confectioner's sugar
1 tablespoon of vanilla extract

Instructions:

1. Prepare the cake:
   Preheat the oven to 175°C.
   Grease and flour two 8-inch round cake pans.
   In a separate bowl, whisk together the oil, sugar, and buttermilk until smooth.
   Add the eggs one at a time, mixing well after each addition.
   In another bowl, sift together the flour, cocoa powder, baking powder, baking soda, and salt.
   Gradually add the dry mixture to the wet ingredients, stirring well.
   Add the vanilla extract and red food coloring, mixing until combined.
   Divide the batter evenly between the pans.
2. Bake:
   Bake in the oven for approximately 25-30 minutes or until a toothpick inserted in the center comes out clean.
   Let cool in the pans for 10 minutes before unmolding and transferring to a wire rack to cool completely.
3. Prepare the filling:
   In a separate bowl, beat the butter until creamy.
   Add the condensed milk, powdered milk, and vanilla, mixing well until smooth. Finally, add the cream to make the filling creamier.
4. Assembly:
   Cut each cake in half horizontally.
   Place one layer of cake on a plate, add some of the filling, spreading evenly.
   Repeat with the other layers.
   If desired, prepare the frosting by mixing the cream cheese, butter, confectioner's sugar and vanilla until smooth and creamy. Use to cover the cake.
5. Finishing:
   Decorate as desired and refrigerate for at least 1 hour before serving so that the filling can set a little.