Melt white chocolate in the microwave until completed melted, approx 2 minutes.
Add the sour cream into the melted white chocolate and begin to mix through.
Roll teaspoon size portions of the mixture in your hands and place on a baking tray.
Pop them into the fridge for an hour to allow harden.
Melt the dark chocolate buttons in the microwave until they also become completed melted.
Add the vegetable oil into the melted chocolate mixture and begin to mix.
Use a toothpick to dip the truffles into the dark chocolate mixture so that they are evenly covered.
If you have paper cases place the truffles into them and put them back into the fridge to cool for a few hours to harden.