Choose 3 or 4 pieces of dried porcini mushrooms, and add them to a small dish. Heat the water either in a pot on the stove or in a kettle. Pour the hot water over the mushrooms, and let them rehydrate as they flavor the water. Keep the mushrooms aside while you prepare the rest of the dry ingredients for the pasta dough.
Step 2
Add the second amount of dried porcini mushrooms to a bullet blender or food processor. Blend the mushrooms until they grind down into a flaky mixture. Make sure there are no chunks remaining. In a large mixing bowl, combine the ground mushrooms with almond flour, xanthan gum, and salt. Make a well in the center of the dry ingredients, and add egg yolks and apple cider vinegar to the center.
Step 3
Mix the wet ingredients together in the center of the bowl, then mix all the ingredients in the bowl together until a dough forms. Pour the warm water the mushrooms were rehydrating in into the dough. You can mince and add the rehydrated mushrooms to the dough as well. Keep mixing until the dough absorbs all the ingredients and comes together. Wrap the dough in plastic wrap, and store it either in your freezer or refrigerator until it’s ready to use.