First attempt Pattern Matching

 def bar(chars: List[Char]): List[(Char, Int)] = {
    def foo(cFoo: Char, accFoo: List[(Char, Int)]): List[(Char, Int)] = accFoo match {
      case Nil => (cFoo, 1) :: accFoo
      case head :: tail => head match {
        case (`cFoo`, y) => (cFoo, y + 1) :: tail
        case (x, y) => (x, y) :: foo(cFoo, tail)
      }
    }
    def blah(cBlah: List[Char], accBlah: List[(Char, Int)]): List[(Char, Int)] = cBlah match {
      case Nil => accBlah
      case head :: tail =>
        blah(tail, foo(head, accBlah))
    }
    blah(chars, Nil)
  }