Preheat the oven to 350 degrees F. Grease a 9x13-inch metal baking pan. Set aside.

In a large bowl, whisk together the melted butter, granulated sugar, and brown sugar until smooth.

Whisk in the eggs and vanilla extract until combined.

Add the flour, cocoa powder and salt. Stir until just combined.

Fold in ¾ cup of the chopped chocolate.

Spread the batter evenly into the prepared pan.

Sprinkle the remaining ¼ cup chopped chocolate over the top.

Bake for 24 to 28 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs. Do not overbake. Let the brownies cool completely in the pan.

In a large bowl, gently fold the Heath Toffee Bits into the softened vanilla ice cream.

Spread the ice cream evenly over the chilled brownies.

Drizzle the salted caramel sauce evenly over the ice cream. If needed, microwave the caramel for a few seconds until it's smooth and easy to drizzle, but don't let it get warm.

Freeze the cake for 30 minutes, or until the ice cream layer is set a little firm.

In the bowl of a stand mixer fitted with the whisk attachment (or using a hand mixer), beat the heavy cream, confectioners' sugar, and vanilla until medium-stiff peaks form.

Spread the whipped cream evenly over the caramel layer.

Sprinkle with the Heath Toffee Bits.

Freeze the cake for at least 4 hours or overnight before serving.

Let the cake sit at room temperature for 5 to 10 minutes before slicing. For clean slices, dip a sharp knife in hot water and wipe it dry between cuts.

Serve with a drizzle of salted caramel sauce on top, if desired.