Take your cup-shaped baking dish of 8 inches and line them with waxed paper to make it moisture-proof. The use of this oiling paper is to avoid the stickiness when prepared. So make sure to have it.
Now take a saucepan and heat the butterscotch chips with a can of sweetened condensed milk. Keep on stirring till the chips melt and mix with milk properly. While stirring keep the pan under the low medium flame.
Take a small bowl and add a vanilla essence with a pinch of salt and mix it. Spread this mixture in a baking dish and refrigerate for 4hrs.
After that, you can take it and cut it shapes as you prefer.
Notes
You can garnish the fudge with peanuts or cashews to have a chewy crunch.