I almost always use cake mixes, and have found that Duncan Hines mixes are a notch above the others available. I also always use 3 eggs, but will need to remember and try your suggestions of milk and melted butter.
My grandmother always preferred Duncan Hines.
As someone born in 1890 who had to learn everything from the VERY old-fashioned way, she really became enthusiastic about new ‘convenience’ foods as they came along.
Sometimes with chocolate mixes, I substitute the water with brewed coffee, and almost always the oil with butter.
Here’s my chocolate frosting recipe: (It’s easy to remember because everything is in 2’s)
2 cups of evaporated milk, or whipping cream
2 cups of sugar
Blend well and slowly bring to a medium rolling boil in a stainless dutch oven or large pot, stirring constantly to prevent sticking, and boil for NINE minutes. You may have to turn heat downward and back up again to prevent boiling over.
Remove from heat. Cool a bit before you add the chocolate to prevent burning it. (If you add it too soon the chocolate will separate from the oil in the chips and in the butter and be a mess. (I know this from experience :-( )
When slightly cooled, stir in
2 cups of dark chocolate chips and
2 sticks of butter.
Stir until melted. When cool enough, transfer to stand mixer and beat until it cools further and thickens. *(If after cooled it is still too thin, add some confectioners sugar a quarter cup at a time until of desired consistence.)
Add one of the following:
2 t. vanilla
or
2 t. creme de cacao
or
2 t. whiskey
Store in fridge until cake is made and cooled. Stir the frosting again before frosting the cake.