That's basically how I do mine, with two differences.
I Use Coconut oil and never butter anymore, because the Coconut oil doesn't seem to take on that bad flavor that butter can get. Also, I let it go for 24 hrs. instead of 4. I keep the crock pot on warm, with the lid cracked. It most likely is really a double De Carb, since I use mine to make brownies, and it get's heated a second time. I feel like keeping it cooler really helps make the flavor pleasant, instead of how it can get, sometimes.
I heard talk last night, of using peanut oil as well. The one advantage over Coconut oil, being that it can take a hotter temp when you go to cook with it.
Happy "Baking" !