Preheat oven to 350 degrees F and line a baking sheet with parchment paper.
Add all ingredients (except bone broth) to a bowl and stir until a batter forms. It should resemble a thick pancake batter in consistency. If it's too thick, add bone broth (or breast milk or water) 1 tbsp at a time until it reaches the right consistency. If too thin, add a bit more flour.
Pour the batter into a piping bag or a plastic resealable bag with one of the corners snipped off.
Pipe the batter on the baking sheet into circles or any shape you want, making sure they don't touch each other.
Bake for 8 minutes, turning the baking sheet halfway through.
Lower the oven temperature to 250 degrees F, then bake for another 20-30 minutes (depending on the shape and size of the puffs), until the puffs are dry to touch and lightly golden on the sides and the bottom. They can get too crunchy and not "melt" if they are baked too long.
Remove from the oven, transfer to the countertop, and cool completely in the baking sheet. The puffs will firm up more as they cool.
Once cooled, you can test the puffs to make sure they soften and melt in the mouth before serving.
Store in an airtight container at room temperature for up to a week.