In large bowl, stir together flour and 1 cup brown sugar; cut in 1/2 cup butter
with fork until fine crumbs form.
Press mixture into 9 x 13-inch baking pan; sprinkle with pecans.
In small saucepan, place remaining 2/3 cup butter and remaining 1/3 cup brown
sugar; cook over medium heat, stirring constantly, until mixture boils. Continue
boiling, stirring constantly, 30 seconds, until sugar dissolves; drizzle evenly
over pecans and crust.
Bake for 18-22 minutes until topping is bubbly and golden; remove from oven.