Pour your Rice Krispies into a large bowl and set aside.
In a small pan mix your karo syrup and your sugar and bring just barely to a boil, stirring constantly. When it just starts to boil, add your peanut butter and mix it in.
Take it off the heat and pour your mixture over your Rice Krispies and mix it all together.
In a well greased 9 x 13″ pan press your Rice Krispie mixture in, just like you would for Rice Krispie treats. You want them in there good but don’t press too hard because you don’t want them too packed in. (I grease my hands and just use them to press the mixture down into place.)
Mix your chips in a bowl and put them in the microwave for 1 minute. About halfway through your minute though, take them out and stir them, then put them back in. When they are good and melted, smear it all over the top of your Rice Krispie layer.
You’re done but you need to let the chocolate set up a little. If you need to rush it, pop them in the fridge for a few minutes (but don’t leave them there because you want them chewy, not hard).