- Preheat oven to 350°F. Line a 9x9 baking pan with parchment paper. 
- Mix graham cracker crumbs and melted butter in a bowl. Press mixture evenly into bottom of pan to form the crust. 
- In another bowl, beat cream cheese and sugar until smooth. 
- Add eggs, Baileys, and peppermint extract. Beat until combined. 
- Stir in green food coloring if using, and fold in mini chocolate chips. 
- Pour cheesecake batter over the crust and spread evenly. 
- Bake for 30 minutes or until center is set. Let cool completely. 
- Melt remaining chocolate chips and drizzle over cooled bars. 
- Chill in the fridge for at least 2 hours before slicing.