In a medium saucepan, combine the whole milk, vegetable oil, and salt. Heat over medium heat until warm but not boiling.
Remove from heat and add the tapioca flour all at once. Stir until fully incorporated; the dough will be thick and sticky.
Let the dough cool for about 10 minutes to avoid cooking the eggs.
Once cooled, add the eggs one at a time, mixing well after each addition. Fold in the grated Parmesan cheese until smooth.
Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
Using an ice cream scoop, portion the dough onto the baking sheet, leaving space between each puff.
Bake for 20-25 minutes or until puffed and golden brown.
Remove from the oven and let cool slightly before serving.
