1Heat oven to 350°F (325°F for dark or nonstick pan). Grease or spray 13x9-inch pan.
2In large bowl, beat cake mix, 1/3 cup butter, the milk and eggs with electric mixer on medium speed about 1 minute or until blended. Spread evenly in pan.
3Bake 8 minutes. Meanwhile, in medium bowl, mix brown sugar, 1/3 cup butter, the pecans and cinnamon. Crumble sugar mixture on partially baked crust to within 1/2 inch of edges. Drizzle caramel topping over sugar mixture to within 1/2 inch of edges.
4Bake 23 to 26 minutes longer (25 to 28 minutes for dark or nonstick pan) or until golden brown and slightly puffed throughout. Loosen edges with knife. Cool 30 minutes. Serve warm or cool. For bars, cut into 6 rows by 4 rows. Store covered.