Preheat oven to 400 degrees Fahrenheit. Line a 10 x 15-inch baking sheet with parchment paper or aluminum foil and spray with nonstick cooking spray.
Place 35-40 saltine crackers in even rows on the prepared pan and set aside.
Heat 1 cup unsalted butter, 1 cup brown sugar, and 1 ½ teaspoons pumpkin pie spice in a medium saucepan over medium-high heat until the sugar has completely dissolved and the toffee mixture is boiling. Boil for 2-3 minutes, or until the temperature reaches 270-290 degrees Fahrenheit.
Pour the toffee mixture over the saltine crackers and use a heat-safe spatula to spread it evenly. Bake for 5 minutes.
Remove from the oven and sprinkle the top evenly with 2 cups white chocolate chips. Let it sit for 5 minutes to allow the chocolate to melt.
Use a spatula to spread the chocolate evenly over the toffee, then sprinkle with ½ cup chopped pecans, regular or candied and a few pinches of pumpkin pie spice. Allow the crack to cool completely and harden before breaking into pieces and serving.
Notes
Leftover Instructions
Room temperature: Store in an airtight container or zip-top bag for up to 7 days.
Refrigerator: Store in an airtight container for up to 2 weeks.
Freezer: Freeze for up to 3 months in a freezer bag or airtight container. Layer parchment between pieces so they don’t stick.