Line your 9x9 inch baking dish with parchment paper, leaving some overhang to make it easier to lift the fudge out later.
In a medium saucepan over medium heat, combine the milk chocolate chips and sweetened condensed milk. Stir continuously until the chocolate is completely melted and the mixture is smooth.
Once your chocolate is melted, remove the saucepan from the heat. Stir in the Baileys Irish Cream and vanilla extract, mixing until well combined.
Pour the fudge mixture into your prepared baking dish. Use a silicone spatula to spread it evenly, smoothing out the top.
Place the fudge in the refrigerator for at least 2 hours or until it is firm.
Once the fudge is set, lift it out of the dish using the parchment paper overhang. Cut it into squares or rectangles, and serve!
