In a heavy 4-quart saucepan, combine cocoa, sweetened condensed milk, water,
orange peel, corn syrup, granulated sugar and brown sugar. Place over medium heat
and stir with a wooden spoon until mixture comes to a boil. Clip on candy thermometer
and cook to 236 degrees F or soft-ball stage.
Remove from the heat and allow mixture to cool to lukewarm.
Meanwhile, butter a 9-inch square baking pan and set it aside.
Add the dates and nuts to fudge. Using a wooden spoon, stir until mixture thickens
and begins to set up. Scrape into prepared pan.
Refrigerate for 3 hours or until firm.
Cut into 1-inch squares.
Serve immediately, or store in an airtight container in the refrigerator.