Step 1

Place the chocolate chips in a heatproof bowl. Microwave in 30-second intervals, stirring well between each spin, until smooth. Cool while you measure the remaining ingredients.

Step 2

Whisk the egg yolks into the warm chocolate, one at a time, followed by the butter. Whisk in 1/2 cup of Bailys until smooth, then set aside.

Step 3

In a large bowl, whisk the remaining Baileys and heavy cream with an electric mixer on medium-low speed until thickened. Add the powdered sugar, increase the speed to medium-high, and beat until medium-stiff peaks form. Gently fold about 3/4 into the chocolate mixture.

Step 4

In a separate, clean bowl, whip the egg whites with a pinch of salt until stiff peaks form.

Step 5

Add a large spoonful of egg whites to the chocolate and whisk until well blended. Then, gently fold the remaining egg whites into the chocolate mixture until no streaks of white are visible.

Step 6

Divide the mousse between 6-8 serving glasses. Top with the remaining Baileys whipped cream and chill for at least 2 hours until set.

Step 7

Before serving, garnish with chocolate shavings. Enjoy!