For ganache: 4 tablespoons of butter, 3 1/2 oz of dark chocolate, 1/5 cups of milk, 1/5 cups of Baileys liqueur. Melt down the oil with low heat, then add the chocolate and sugar. Stir and warm everything up well.
In another container, mix the dry ingredients: flour, salt, soda and loosener.
Whisk the eggs and gently put them into the chocolate mixture. Also add the flour mixture to the chocolate mixture in portions. Mix with a spoon or spatula, but do not whisk with a mixer.
While the cupcake is baking, prepare the ganache. Pour the milk into the saucepan, heat a little, then add the chocolate and liqueur. Do not let the mixture to boil, but it should warm up well. Remove from the heat and then add the oil. The ganache texture should be homogeneous. Let the cupcake to cool down a little before pouring it with ganache.
Enjoy your meal!