How to make my double jump require 2 separate button presses?

Hello! I'm currently going through the tutorials and I've made my own double jump as I tinker around on my own. The problem is, since Update() is checking every single frame to see if the player is pressing jump, what ends up happening is the following:

Frame 1: The player is holding jump, AddForce(); Frame 2: The player is still holding jump, AddForce();

I end up effectively with a jump that jumps twice as high as it should unless the player taps the jump button for exactly 1 frame. Below is my code. I notice that the Input API has "GetKeyDown" which sounds like it would help my problem, but I want to utilize the InputManager/GetAxis so I can have customizable controls for my hypothetical future game. Below is my code:

 void Update(){
         float jumping = Input.GetAxis("Jump");
         if (grounded && jumping > 0 && jumpCount == 0) { //THE JUMP
             GetComponent<Rigidbody2D> ().AddForce (new Vector2 (0, jumpForce));
             anim.SetBool ("Ground", false);
             jumpCount++;
             Debug.Log ("Wee!" + jumpCount);
         } else if (jumpCount < 2 && jumping > 0) {
             GetComponent<Rigidbody2D> ().AddForce (new Vector2 (0, jumpForce));
             Debug.Log ("Double Jump!");
             jumpCount++;
         }

Thank you very much for your time!