Line 8-inch pie pan with plastic wrap. Set 6-oz. custard cup upside down in center.
In medium bowl, combine cream cheese, Gouda cheese and mayonnaise; mix until well blended. Stir in dried beef and onions. Spoon cheese mixture into pie pan around custard cup, smoothing and packing firmly with rubber scraper. Cover tightly with plastic wrap. Refrigerate several hours or until firm.
To serve, uncover ring; turn upside down onto serving plate. Remove plastic wrap and custard cup. Cover top of ring with parsley, pressing in lightly. Garnish with pimiento pieces. Serve with crackers.