I think this is just what you're looking for, hope you enjoy the clone I came up with...

PEANUT BUTTER CRISP
Source: Kathleen
Serves/Makes:2 (4x4-inch) hunks

1/4 cup (60 ml) creamy peanut butter
1 3/4 cups (425 ml) white chocolate chips
1 cup (225 ml) Rice Crispies cereal
1/2 cup (125 ml) (slightly packed) mini marshmallows
1/4 cup (60 ml) semi-sweet chocolate chips (frozen)

In double boiler over medium-high heat, add white chocolate chips and peanut butter. Constantly stir with wire wisk until completely melted. Remove from heat (and remove off bottom boiling water). Set aside and let cool for about 5 minutes.

Transfer peanut butter mixture to a mixing bowl. Fold in all of the rice crispies. Let cool till it barely feels warm (if you add the marshmallows and semi-sweet chocolate chips when it's too warm, they will melt and that's not what you want). It will take a while to cool, but do not cool it down in the refridgerator or it will set up.

While you wait, line a 4x8.5-inch loaf pan with plastic wrap. You may even want to lightly spray the plastic with cooking spray first for easier removal.

When the mixture is cooled, fold in marshmallows first then the semi-sweet chips (just fold to distribute, don't over work the mixture).

Pour the mixture into the prepared pan, fold the excess plastic wrap over top and gently press the mixture so it's even in the pan. The harder you press, the denser the bark will be.

Now it's time to put in the fridge to set it up. It will take about 20 to 30 minutes to completely set up.

When set, remove from pan and cut into desired size pieces.

Comments
If you are a real fan of peanut butter, add extra. It is however very overpowering, so be careful. I tried this out a few times and this came so close to the real thing I couldn't tell the difference! I had both in front of me at the same time. you have any questions, just post them and I will check back... enjoy!