Preheat the oven to 450°F. Lightly butter four 4 ounce ramekins.
Place the butter and chocolate in medium glass bowl; microwave on high for about 2 minutes, stirring twice, until butter and chocolate are melted.
Remove the chocolate from the microwave and let cool until no longer hot to touch. Add the eggs, sugar and 1 tablespoon Irish Cream; beat with an electric mixer until foamy. Beat in the flour until just combined.
Pour equal amounts of batter into the ramekins and bake for 8 to 10 minutes or until set around the edges and soft in the middle.
Let stand for 5 minutes, then invert onto 4 small plates. Pour 2 tablespoons of liqueur around each dessert. These are most delicious when served warm.