Heat oven to 350 degrees F. Line a 13 x 9 x 2-inch baking pan with foil. Grease foil. Crush granola in heavy-duty plastic bag with rolling pin. Pulse together crushed granola, flour, sugar and salt in food processor or blender until well combined. Add butter; pulse until evenly distributed.
Pour granola mixture into prepared pan. Press evenly over bottom. Top granola crust with trail mix, spreading in even layer over crust. Sprinkle with semisweet chips.
Drizzle condensed milk over trail mix, covering as much as possible.
Bake in 350 degree F oven 25 minutes or until lightly golden. Let cool in pan on rack. Use foil to lift bar from pan. Cut into squares or rectangles and serve. Makes 24 bars.