Preheat oven to 350°F. Line an 8-inch baking pan with aluminum foil, shiny side down. Lightly spritz the foil with a nonstick cooking spray.
In a food processor, crush the Brownie Brittle pieces until they're reduced to about 1 cup of crumbs.
In a medium bowl, mix the crumbs with the sugar. Add the melted butter and stir well until the crumbs are all evenly coated.
Press the crumb mixture into the bottom of the prepared baking pan. Use your fingers or a clean drinking glass to pack the crust down tightly and evenly.
Bake until the edges of the crust just begin to harden, about 20 minutes. Set the crust aside to continue hardening as it cools.
In a large bowl, use an electric mixer to beat together the softened cream cheese and sugar until the mixture is light and fluffy. Add the flour, mixing only until it is well combined.
In a small microwave-safe bowl, melt the chocolate in the microwave at 50% power in 20-second intervals. Stir between each interval until the chocolate is smooth and uniformly melted.
Stir the melted chocolate, vanilla, Greek yogurt, and egg white into the cheesecake mixture. Beat until just combined. Fold in the butterscotch chips.
Pour the cheesecake mixture into the baked crust and smooth it out. Sprinkle the top with the remaining Brownie Brittle crumbs.
Bake until the cheesecake just feels set but the center looks a little jiggly, about 25-30 minutes.
Let the cheesecake cool on the countertop for 20 minutes. Chill it in the the refrigerator for at least 3 hours or overnight.
After it's completely chilled, use the foil to help lift the cheesecake out of the baking pan.
Slice into bars and serve cold.
