1. Line 14-inch pizza pan with heavy-duty aluminum foil.
2. Melt 1-1/2 cups chocolate pieces and 1-1/2 tablespoons shortening in small pan or bowl set over hot, not boiling, water, until smooth. Add nuts.
3. Using thin metal spatula, spread chocolate mixture over bottom of pizza pan. Refrigerate 1 hour or until firm.
4. Meanwhile, toast coconut in large skillet over medium heat, stirring occasionally, until lightly golden, 3 minutes. Remove to paper toweling.
5. Invert crust onto work surface. Peel off foil, being careful not to break crust. Return crust to pizza pan and refrigerate.
6. Beat cream cheese, strawberry jam and vanilla in small bowl until well blended. Carefully spread over chocolate crust to within about 1/2 inch of edge. Sprinkle with candy-coated chocolates and coconut. Return to refrigerator.
7. Melt remaining semisweet chocolate pieces and shortening in small pan or bowl set over hot, not boiling, water, until smooth. Drizzle thin stream over top of pizza. Sprinkle with grated white chocolate. Serve immediately or refrigerate until ready to serve.