Preheat oven to 375°.
Beat the first 4 ingredients with a mixer at medium speed until well-blended. Lightly spoon flour into dry measuring cups, and level with a knife. Add flour to sugar mixture, stirring until well-blended. (Mixture will be crumbly.) Firmly press mixture into bottom of an 8-inch square baking pan coated with cooking spray. Bake at 375° for 15 minutes.
While crust is baking, combine milk and caramel candies in a medium sauce-pan. Place over low heat; cook until candies melt, stirring occasionally. Stir in 1 teaspoon vanilla; remove from heat.
Remove the crust from oven. Pour the caramel mixture evenly over hot crust. Sprinkle with pecans. Bake at 375° for 15 minutes. Cool completely on a wire rack.