Preheat oven to 375°. Microwave first 3 ingredients in a large microwave-safe bowl at HIGH 1 to 1 1/2 minutes or until melted and smooth, whisking at 30-second intervals.

Whisk sugar and flour into chocolate mixture. Add eggs, 1 at a time, whisking just until blended after each addition. Whisk in vanilla and salt. Stir in pecans. Pour mixture into pie shell.

Bake at 375° for 35 to 40 minutes or until set. Cool 10 minutes before serving. Serve with ice cream.