We'd like to help, but you HAVE to give more information than this.
You've basically said you're "making cake" but we have no idea if it's angel food cake, pound cake, or fudge cake. They're all different and troubleshooting problems depends on what kind of "cake" you're making and how you made it..
So please provide the recipe (ALL ingredients, including water and additives, and ALL in weights) and the method you used to make the soap.
And explain more -- At what stage is this soap "too foamy"? What did you do to get to this point?