Place the milk, cream cheese, brown sugar, vanilla and salt in a blender; cover and process until smooth. Add cream; process on low speed just until combined.
Fill cylinder of ice cream freezer; freeze according to manufacturer's directions. Transfer to a freezer container; freeze for 4 hours or until firm.
For shakes, in a blender, combine beer and 2 cups ice cream; cover and process until smooth. Pour into chilled glasses; top with whipped cream and pretzels. Serve immediately.
