Heat oven to 350 degrees F and position a rack in the bottom third. Line an 8-inch
square baking dish with a 12-inch square of aluminum foil, shiny side up. Gently
press the foil into place. Lightly butter the foil.
Spread pecans in a shallow baking pan and toast in the oven for about 12 minutes
or until very hot and fragrant. Set aside.
Using a large sharp knife, cut the Heath bars crosswise 1/4 to 1/2 inch thick.
This should make about 1 1/2 cups.
Chop a scant 1/4 cup of the bars into smaller pieces and reserve.
In a small double boiler, melt the unsweetened chocolate and the stick of butter
over warm water, stirring occasionally. Set the chocolate aside to cool slightly.
In a medium bowl, using an electric mixer, beat the eggs, sugar, vanilla extract
and salt at medium speed until mixed.
Add melted chocolate and beat only to mix.
Add flour and beat at low speed just until incorporated.
Using a wooden spoon, stir
in the toasted pecans and all but the reserved 1/4 cup of the Heath bars.
Pour the batter into the prepared pan and spread smooth.
Sprinkle the remaining 1/4 cup Heath bars on top.
Bake the brownies for 28 minutes, or until a wooden pick inserted in the center
comes out just barely clean.
Transfer to a rack to cool.
Remove from pan and cut into small squares with a serrated knife.