Brazilian Cheese Balls {Pao de Queijo}

http://blogs.babble.com/family-kitchen/2011/05/22/brazilian-cheese-bread/
Brazilian Cheese Balls {Pao de Queijo}

2 cups whole milk
8 tablespoons butter, melted
1/2 cup vegetable oil
4 1/4 cups tapioca flour
4 eggs
2 cups grated asagio or parmesan cheese
1/4 cup grated sharp cheddar cheese
salt to taste

Preheat the oven to 350 degrees. Mix milk, salt, vegetable oil and butter in a pot, and bring to a boil. As soon as it boils, remove from heat and stir tapioca flour into the milk and butter mixture. Allow mixture to cool slightly before adding the eggs and the cheese, and mix well. With floured (tapioca flour) hands, shape the dough into golf ball size balls (about 50 gram portions) and place them on a baking sheet. Bake rolls for 20 to 25 minutes, until they are puffed up and are golden. They will rise slowly and puff up mostly in the last 5 or 10 minutes.