Preheat oven to 350 degrees. Butter and flour a 13-by-9-inch baking dish.
In a mixer bowl, beat 10 tablespoons butter until light and fluffy.
In a separate bowl, whisk together 6 tablespoons cocoa, 1 cup sugar and ¾ cup flour.
In a small bowl, lightly whisk together 2 eggs and 1 teaspoon vanilla. Add egg mixture alternating with cocoa mixture to butter until well-incorporated. Stir in ½ cup walnuts.
Spread mixture evenly in prepared pan. Bake 5 to 6 minutes, until the batter has risen in the middle. Remove from oven and tap pan firmly on the counter to make brownies fall. Be careful; some batter might splash out at this point. Place brownies in oven for another 5 to 6 minutes. Brownies will not be fully baked at this point. Cool to room temperature, then refrigerate at least 3 hours, or until thoroughly chilled.
In a double boiler, heat the caramels with 1 tablespoon butter and 4 tablespoons of the cream until melted and smooth. If necessary, stir in remaining 2 tablespoons cream to achieve a consistency that is pourable when warm, and thick but oozing at room temperature.
Pour caramel mixture over chilled brownie layer, taking care to push the caramel into the corners. Sprinkle with the chocolate chips. Freeze at least 4 hours, until caramel is very firmly set.
Make another batch of brownie batter, as before. Carefully spread batter over the frozen caramel and chips layer, being careful not to disturb the caramel or chips.
Bake at 350 degrees for about 30 minutes, or until the center looks done. Because of the chocolate-and-caramel layer, using the toothpick test or shaking the pan are not good methods to determine doneness. Brownies will fall as they cool; this is desirable.
Cool to room temperature, then refrigerate overnight. This allows the caramel-and-chocolate-chip layer to set.
Cut into squares and dust with confectioners’ sugar. Store in the refrigerator or freeze. Bring to room temperature to serve.
Editor’s note: If you can’t find Belgian chocolate chips, you can chop semisweet Belgian chocolate into small pieces. You can also use regular semisweet chocolate chips, although the flavor might not be the same.