A product like this has been marketed for black men for years. It's called Magic or Magic Shave by SoftSheen Carson, and lots of people swear by it. They make it in a cream and in a powder. Is this what you have?
I've personally never used it, but I have a tube of the regular strength stuff sitting right here (I started to get really bad razor bumps on my neck). There are a few similar products, but my problem is that they're always plastered with so many warnings I'm hesitant to use them. For example, this stuff says, if this is your first time using Magic, you should use the mild cream, and you shouldn't use it within 36 hours of shaving with a shaver or razor, and not after washing your face, or with any after shave product containing alcohol, or after prolonged sun exposure. And, if you mess up, you have to wait 24 hours before trying again.
There are just so many stipulations with using depilatories. But hey, a lot of guys use them with great results. I just don't want to be the one person who breaks out in hives from using this stuff.
I found your original post funny because our situations are so similar. I had a combination that worked, too. Now, I can't prevent the razor bumps on my neck if I shave with a razor, so I've taken to using an electric shaver. It doesn't cut as close, so the hairs don't grow back in. It's been working out pretty well lately.
But on a related note, the one shaving cream that did prevent razor bumps best was Neutrogena Men Razor Defense Shave Cream.