I remember when we started to mix better butter in the blender instead of how we had been doing it before--I think with the hand mixer (not literally by hand...?) I remember how smooth and homogeneous the texture was when using the blender--instead of a little grainy and prone to separation, as it had been before.

I wonder that I was never ever the one to make better butter. I don't even know the ratios. However, all you do is combine softened butter with olive oil (I think in equal parts, or with slightly more butter to oil). Don't use better butter for cooking eggs in a frying pan, though--for them not to stick, butter alone works better.