Line an 8-inch square pan with a parchment sling and lightly mist the parchment.
In a large pot over low heat, melt the butter. Add 10 ounces mini marshmallows and stir gently until just melted and smooth. Remove from heat.
Stir in the caramel extract. Add the Rice Krispies cereal and the crushed freeze-dried apples. Use a lightly greased silicone spatula to fold until everything is coated.
Scrape the mixture into the prepared pan. Lightly press into an even layer. Don’t pack it down or the bars will be firm.
Warm the caramel sauce until pourable and drizzle over the top. Let set for 20 minutes, then lift out with the parchment and cut into 8 large or 16 smaller squares.
Notes
Make sure to use freeze-dried apples, not fresh, to avoid soggy bars.
Store at room temperature in an airtight container for 2 to 3 days. If stacking, add parchment between layers so they don’t stick.