Preheat the oven to 375˚F (190˚C). Line a baking sheet with parchment paper.
2. Step
In a medium bowl, whisk together the flour, salt, and baking powder.
3. Step
In a large bowl, combine the oil, melted butter, sugar, and cocoa powder and whisk.
4. Step
Add the egg and vanilla and mix until the ingredients are incorporated.
5. Step
Add the flour mixture, and mix thoroughly with a spatula.
6. Step
Roll the dough into 2-inch (5-cm) balls. Press a truffle into each dough ball and wrap the dough around so the truffle is not exposed. Place onto a parchment paper covered baking pan.
7. Step
Bake for 10 minutes, until the dough is slightly firm to the touch.
8. Step
Dust with powdered sugar. Can be stored in an airtight container up to 5 days. Reheat in the microwave for 20 seconds before eating.
