Preheat oven to 350°F. Grease a 9x9-inch baking pan.

Sift together the flour and salt; set aside.

Melt butter and chocolate chips in a saucepan over low heat, stirring until smooth.

Remove from heat, stir in sugar, and let cool for 3 minutes.

Beat eggs into the chocolate mixture one at a time. Mix in Baileys Irish Cream.

Stir in the flour mixture with a wooden spoon.

Spread batter into the prepared pan.

Bake for 30-35 minutes until a toothpick comes out clean.

Allow to cool in the pan on a wire rack.

Prepare frosting by blending softened butter, powdered sugar, and Baileys Irish Cream until smooth and creamy.

Spread the frosting over cooled brownies and serve.