Gently heat the cream in a pan. When hot, remove from the pan and leave to stand for 1 min. Add dark and milk chocolates to the pan, and stir until melted and smooth. Pour mixture into a bowl and chill in the fridge until firm.
When the chocolate is firm, use 2 teaspoons to scoop out 12 walnut-sized truffles. Roll half the truffles in the cocoa powder and the other half in hazelnuts. Place the covered truffles in mini paper cases and pop into egg boxes. You can now tie up with ribbon and give to someone you love.