Rspec:: allow every instance to receive a message

I want to mock a method for every instance of a class. if I allow_any_instance_of then it works great if instance_count = 1

However if I have many instances of the same class the second instance isn't caught by the mock.

I'm attempting to get a pile of tokens from different sites. But during testing I don't really need "real" tokens. So I plan to mock get_token to return '1111'.

class Foo
  def children
     [Bar.new, Bar.new] #....
  end
  def get_tokens
     children.map(&:get_token) || []
  end
end

so now how do I not mock out the get_tokens?