Preheat oven to 350 degrees. Line cookie sheets with parchment paper. Sift flour and corn starch together. In a bowl, combine butter and cream cheese. Add sugar and mix well. Then add lemon juice and milk, mix well. Add flour and corn starch mixture and mix well. Then add white chocolate chips and mix well.
Form into 1-inch balls and place them on parchment paper lined cookie sheets. Bake for 15-18 minutes. Makes 2 1/2 dozen.