You can sweeten your nut butter to your liking but this is my preferred ratio:
• 2/3 cup Nut Butter (plain, smooth, no added ingredients - if you make your own, that's even better - should be kind of runny)
• 2-4 Tbsp Honey (4 is pretty sweet, start with 2 and work up from there if you think it needs it)
•1/8 tsp Salt
Stir everything together until you have a thickened nut butter. The honey will cause the runny nut butter to seize up a little (just like adding water to chocolate). This makes it much easier to pipe into the molds, as well as keeping it from oozing out once you bite into the chocolates.
Transfer the nut butter to a piping bag (I like to fit mine with a large open tip for easier and ore accurate piping but it's not necessary). Cut off the tip and pipe into your prepared molds/shells.