Bring the butter to room temperature before cooking. Put the butter with all the ingredients in a tall container and mix thoroughly with the mixer. Let it steep for at least 2 hours and then try, adding some seasoning if necessary. Be careful with the chili paste, it only comes into its own after a while.
I use a Chilean chili paste. Depending on the sharpness of the paste or your personal sharpness tolerance, it is better to slowly approach the sharpness and use a little less chili paste at first.