Line an 8×8-inch pan with parchment and spray lightly.
Microwave the flour for 1 minute to heat-treat.
Freeze 1 cup chocolate chips for 15 minutes.
Cream butter, sugars, milk, vanilla, and salt.
Add cooled flour and mix well.
Melt white chocolate and condensed milk until smooth.
Stir in frozen chocolate chips and combine.
Pour into pan, top with remaining chips, chill 2 hours.
