Combine all the ingredients in a small sauce 1 qt sauce pan and heat the mixture until hot but not boiling, and the garlic begins to sizzle, then remove the pan from the heat and allow to cool and infuse overnight for the best flavor.
After the oil has infused, strain and reserve it until needed. The flavor will keep better under refrigeration.
Notes
This makes a little more than you'll need for preserving the mushrooms. Play with the flavors however you want, but traditionally olio santo is only made with garlic, chili, lemon and bay.