Add bones to a slow cooker or stock pot and cover with filtered water. Add apple cider vinegar and any aromatics like vegetables, herbs or spices.

Bring to a boil then reduce to a simmer. Simmer for at least 6 hours, up to 48 hours for beef bones. Skim fat and foam as needed.

Once broth is done simmering, remove from heat. Carefully strain out all solids using a fine mesh strainer.

Let cool slightly. Then refrigerate overnight so the fat solidifies on top and is easier to remove.

The next step is to boil the broth down to reduce and concentrate it. This makes it easier to dehydrate.

Pour defatted broth back into a pot. Bring to a boil, then reduce heat and simmer uncovered. Stir frequently and simmer until reduced to about 1/3 original volume.

Broth is ready when it coats the back of a spoon and is syrupy. Be careful not to burn.

Now we'll remove the remaining moisture from the concentrated broth to turn it into a powder. This can be done in a dehydrator or oven.

Line dehydrator trays with non-stick sheets. Silicone sheets work best.

Carefully pour broth onto sheets in a thin layer, about 1/4 inch thick

Dehydrate at 135°F to 155°F for 8 to 48 hours, checking often.

Broth is done when completely dry and brittle.

Line baking sheets with parchment paper.

Pour broth in a thin layer onto sheets, no more than 1/4 inch thick.

Bake at 170°F for 6 to 12 hours.

Rotate pans and check often to prevent burning.

Broth should be dry and brittle when done.

Once fully dehydrated, the broth will be dry, flaky and brittle. Break into pieces and grind into powder using a blender or food processor.

Grinding it yields a fine powder that easily rehydrates into broth later on. Store bone broth powder in an airtight container.