Lay out a large piece of parchment paper. This should be large enough to fit a 10" x 16" rectangle with room around each side.
In a heavy duty, thick bottomed pot, combine butter, brown sugar, salt, evaporated milk, heavy cream, and corn syrup.
Cook over medium- low heat, stirring constantly, until butter has melted and sugar has dissolved.
Turn heat to medium. Stirring constantly, bring mixture to a boil.
Turn heat to medium high. Stirring constantly, cook caramel until temperature reaches 241F.
Turn off heat. Pour caramel on parchment. Spread into a thin layer, making a 10" x 16" rectangle. Cool completely. Make vanilla cream while it cools
Vanilla Cream
Place shortening in mixing bowl. Mix on low for one minute.
Add powdered sugar, ½ cup at a time.
Add vanilla and corn syrup. Mix until combined. Ingredients will resemble goat cheese crumbles.
Add water. Mix. A small amount of additional water might be needed to achieve texture. You are looking for the ingredients to feel like play-doh and to become like clay when you squeeze them together in your hand.
Dump out contents of mixing bowl onto work surface (parchment paper or a large cutting board is great!) Work the ingredients until a dough forms. Set aside.
Assembling Caramels
Cut caramel slab into four equal pieces.
Apply vanilla cream in a thin layer to caramel, leaving ½ " space at the top long side. Vanilla cream layer should be about half the height of the caramel layer.
Roll up caramel into a log.
Using your hands, roll caramel long like you are rolling pretzel dough to lengthen it. Aim for 12-15 inches in length. You should no longer hear or feel a caramel seam when rolling the piece.
Cut the caramel into ½" slices. Wrap in desired packaging.