Spray a 13x9-inch baking pan with cooking spray.

Combine the crispy rice cereal and 2 cups of the miniature marshmallows in a large bowl. Set aside.

Combine the sugar and the 3/4 cup Karo® syrup in a medium saucepan. Bring to a boil over medium heat, stirring occasionally. Once at a boil, let it boil for one minute. Remove from the heat and stir in the almond butter and pumpkin pie spice until smooth. Pour over the cereal mixture and quickly stir to coat*. Press evenly into the prepared pan.

In a medium microwave safe bowl, combine the white chocolate chips, cream and 2 tablespoons Karo® syrup. Cook on high in 10-15 second increments, stirring often, until the chips are melted and the mixture is smooth. Spread the mixture over the top of the cereal layer and top with the remaining 2 cups of marshmallows.

Arrange a rack in the oven or broiler so the top of the pan is 4 inches from the source of heat. Preheat the broiler. Broil the bars just until the marshmallows are lightly browned, 10-30 seconds.

Cool completely then cut into 2-inch squares.