Heat the oven to 200 C. Butter and sugar, whisk until fluffy, add egg one at a time. Mix the liqueur with the cream, pour in the oil. mixture. Sift the flour, starch, vanilla, cocoa and baking powder. Add flour mixture to oil in 3 stages, stirring the batter after each addition. RUB chocolate, pour in the batter. Put the dough in cupcake molds 2/3 full and bake for about 20 minutes.