Steps
1. Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper.
2. In a medium saucepan, combine the butter, margarine, and 1/2 cup of water. Bring to a boil over medium heat.
3. In a separate bowl, whisk together the tapioca flour, Parmesan cheese, mozzarella cheese, and a pinch of salt.
4. Once the butter mixture is boiling, remove it from the heat and slowly add the tapioca flour mixture, stirring constantly until well combined.
5. Allow the mixture to cool for a few minutes, then add the eggs one at a time, mixing well after each addition.
6. Using a spoon or a cookie scoop, drop small portions of the dough onto the prepared baking sheet, leaving some space between each puff.
7. Bake in the preheated oven for 15-20 minutes, or until the puffs are golden brown and crispy.
8. Remove from the oven and let cool slightly before serving.