Preheat your oven to 350 °F.
Line the bottom of 3(8-inch) cake pans withparchment paper circles.
Thengrease the sides of pans with cooking spray.
Forcake: in a medium bowl, blend togetherthe flour, pudding mix, baking powder andsalt.
In a large bowl, add the brown sugar, butter and vegetable oil and beat untillight and fluffy.
Add the eggs and vanilla extract and beat until well blended.
Add half of the flour mixture and mix until justblended.
Add the milk and mix until well blended.
Add the remaining flour mixture and mix until well blended.
Divide the mixture into the prepared cakes pans evenly.
Bake for about 22-25 minutes.
Remove the cake pans from oven and place onto the wire racks to cool for about 2-3minutes.
Then invertthe cakes onto the racks to cool completely.
Forfrosting: in a large bowl, add the butter and beat until smooth.
Slowly add the melted butterscotch chips and mix until well blended.
Add half of the powdered sugar, half of cream and salt and mix until well blended.
Add the remaining powdered sugar and mix until smooth.
Add the remaining cream and mix until smooth.
Arrange 1cake onto a serving plate.
Spread about 1 cup of frosting over the cakein an even layer.
Now,arrange the second cake on top of frosting.
Spread another q cup of frosting on top of second cake in an even layer.
Place the third cake on top of frosting.
Spread the frosting on top and sides of cake evenly.
Cut the cake into desired-sized slices and serve.