Whenever I make truffles, I rarely use alcohols. I occasionally use Kahlua, but that's really it. I usually use LorAnn oils (sold in many cake supply stores and even in Michaels, Hobby Lobby, etc.). They can also be found on their website, here:
https://www.lorannoils.com/c-2-lorann-gourmet.aspx
Caution: When using these, a little goes a long way. This isn't like a vanilla extract. Usually for a large batch of handpainted chocolates or truffles I only use a couple of drops. They come in a HUGE variety of flavors and mix and match very well.
Happy baking

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