In a stand mixer, beat peanut butter, vanilla extract, and salt together until smooth and well combined.

Add cereal, beat well, until cereal is broken up and fully incorporated.

Add powdered sugar, beat on low until sugar is completely mixed in.

With clean hands, knead mixture slightly to bring together.

Divide into 8 equal sized balls, roll into logs about ¾" in diameter.

Freeze while you prepare the dipping caramel:

In a large saucepan, combine everything except the vanilla extract.

Bring to a boil over medium heat, stirring constantly.

Once boiling, affix a candy thermometer to the pan. Make sure the tip of the thermometer is in the sugar mixture, but not touching the bottom of the pan.

Boil - stirring constantly - until mixture reaches 240 F (115 C).

Allow to cool for 5 minutes, before dipping anything in it.

Line a baking sheet or flat work area with parchment paper.

Carefully dip your frozen filling logs into the warm dipping caramel.

Allow excess to drip off, before transferring to parchment paper. Allow to cool and fully set before proceeding.

Either in the top of a double boiler - or in a glass bowl, microwaved for 30 seconds at a time - carefully melt chocolate and shortening together, stirring well until smooth.

If chocolate is too thick for dipping, add a little more shortening, once again stirring well until smooth.

Carefully dip each bar into chocolate, allow excess to drop off, and transfer back to parchment paper.

Keep chocolate warm while dipping, as it thickens as it cools.

Allow bars to set before transferring to covered storage container.