I use the peanut oil, powder, and butter in my recipe. It all blends in quite well without any additional prep. I add it all in at trace. I actually have 2 recipes. One calls for 1 Tbls. butter and 2 Tbls. powder and comes out a delightful peanut butter color. The other I put a 1/4 of a cup peanut butter, peanut oil and 1 Tbls. powder and this gels nicely and is a rich brown. Both make a nice hard bar and both smell peanutty. Using just peanut oil is just fine but it doesn't smell like peanut butter. If you do that I would add some peanut butter f.o. The soap is not as creamy a lather with just peanut oil either. Like all butters, they add richness.