1Line an 8x8 inch baking dish with parchment paper or lightly grease it.
In a medium saucepan, combine the sweetened condensed milk and chocolate chips.
Heat over medium-low heat, stirring constantly, until the chocolate chips are completely melted and the mixture is smooth.
Remove the saucepan from the heat and stir in the vanilla extract.
Pour the mixture into the prepared baking dish and spread it evenly.
Let the fudge cool to room temperature, then refrigerate for at least 2 hours or until firm.
Once the fudge is set, cut it into squares and serve.