2 c. flour
1 c. packed brown sugar
1/2 c. butter
1 c. pecan halves (not chopped)

FILLING:

2/3 c. butter
1/2 c. packed brown sugar
1/2 c. butterscotch pieces
1/2 c. semi-sweet chocolate pieces

Preheat oven to 350 degrees. Combine all crumb mixture ingredients. Beat at low speed, scraping side of bowl often, until particles are fine (1-2 minutes). Press into ungreased 13 x 9 inch pan. Sprinkle pecans evenly over unbaked crumb mixture.

Prepare filling by boiling sugar and butter in a heavy saucepan and cooking over medium heat, stirring constantly, until mixture boils all over the top (4-5 minutes). Boil 1 minute, stirring constantly. Pour filling evenly over pecan and crumb mixture. Bake for 18-20 minutes or until entire filling is bubbly. Immediately put butterscotch and chocolate pieces on mixture and let melt slightly (2-5 minutes), slightly swirling pieces as they melt. Leave some whole for a marbled effect. Do not spread pieces. Cool completely and cut into bars.