Make the Crumb Base
Grease a 9-inch square pan and set aside. In a heavy saucepan, combine butter, sugar, cocoa, vanilla extract, egg, and salt. Cook over low heat, stirring constantly until mixture coats a spoon (this creates a custard-like base). Remove from heat and stir in graham cracker crumbs, coconut, and pecans. Spoon into prepared pan and press evenly.
Prepare the Cream Filling
In a mixing bowl, cream together softened butter, cream cheese, and instant vanilla pudding mix. Beat in confectioners sugar and milk until smooth and fluffy. Spread evenly over the graham cracker base. Refrigerate for 30 minutes or until the pudding layer is firm.
Add the Chocolate Glaze
In a double boiler over hot (not boiling) water, melt semisweet chocolate and butter together, stirring until smooth. Spread evenly over the chilled pudding layer. Refrigerate again until the chocolate is completely firm, at least 1 hour.
Cut and Serve
Once fully set, cut into 1.5-inch squares. For clean cuts, dip your knife in hot water and wipe dry between cuts. Store in the refrigerator in an airtight container.