Add sweetened condensed milk, vanilla extract, chocolate chips, Nutella, and butter to a glass bowl
Mix together well
Microwave for 15-20 seconds at a time, stirring between each interval, until everything is melted, smooth, and thickening (approximately 3 minutes total)
Line an 11 x 7 baking dish with parchment paper and spray with cooking spray
Pour fudge into baking dish and sprinkle sea salt on top
Refrigerate for at least 2-3 hours to set up
Cut into bite-sized pieces and keep refrigerated when not eating
