diff --git a/system/HTTP/Response.php b/system/HTTP/Response.php
index 40911e38096d..2c1e25ea8fb5 100644
--- a/system/HTTP/Response.php
+++ b/system/HTTP/Response.php
@@ -640,7 +640,7 @@ public function send()
 		{
 			$this->CSP->finalize($this);
 		}else{
-		    
+
 			$this->body = str_replace(['{csp-style-nonce}','{csp-script-nonce}'], '', $this->body);
 		}
 
@@ -911,6 +911,35 @@ public function getCookie(string $name, string $prefix = '')
 		}
 	}
 
+	/**
+	 * Sets a cookie to be deleted when the response is sent.
+	 *
+	 * @param        $name
+	 * @param string $domain
+	 * @param string $path
+	 * @param string $prefix
+	 */
+	public function deleteCookie($name, string $domain = '', string $path = '/', string $prefix = '')
+	{
+		if ($prefix === '' && $this->cookiePrefix !== '')
+		{
+			$prefix = $this->cookiePrefix;
+		}
+
+		$name = $prefix.$name;
+
+		foreach ($this->cookies as &$cookie)
+		{
+			if ($cookie['name'] == $name)
+			{
+				$cookie['value'] = '';
+				$cookie['expires'] = '';
+			}
+		}
+
+		return $this;
+	}
+
 	/**
 	 * Actually sets the cookies.
 	 */
diff --git a/system/Helpers/cookie_helper.php b/system/Helpers/cookie_helper.php
index 616ab9a60dbe..730339712349 100755
--- a/system/Helpers/cookie_helper.php
+++ b/system/Helpers/cookie_helper.php
@@ -126,7 +126,7 @@ function get_cookie($index, bool $xssClean = false)
 	 */
 	function delete_cookie($name, string $domain = '', string $path = '/', string $prefix = '')
 	{
-		set_cookie($name, '', '', $domain, $path, $prefix);
+		\Config\Services::response()->deleteCookie($name, $domain, $path, $prefix);
 	}
 
 }
diff --git a/tests/_support/HTTP/MockResponse.php b/tests/_support/HTTP/MockResponse.php
index 01e7b3e4d948..8b2331c006c2 100755
--- a/tests/_support/HTTP/MockResponse.php
+++ b/tests/_support/HTTP/MockResponse.php
@@ -7,80 +7,11 @@
  */
 class MockResponse extends Response
 {
-    public function setCookie(
-        $name,
-        $value = '',
-        $expire = '',
-        $domain = '',
-        $path = '/',
-        $prefix = '',
-        $secure = false,
-        $httponly = false
-    )
-    {
-        if (is_array($name))
-        {
-            foreach
-            (
-                [
-                    'value',
-                    'expire',
-                    'domain',
-                    'path',
-                    'prefix',
-                    'secure',
-                    'httponly',
-                    'name'
-                ] as $item
-            )
-            {
-                if (isset($name[$item]))
-                {
-                    $$item = $name[$item];
-                }
-            }
-        }
-
-
-        $_COOKIE[$prefix . $name] = $value;
-
-        /*
-            @todo: Find a way to use setcookie()
-            without it throwing header issues.
-            setcookie
-            (
-                $prefix.$name,
-                $value,
-                $expire,
-                $path,
-                $domain,
-                $secure,
-                $httponly
-            );
-        */
-    }
-
-    //--------------------------------------------------------------------
-
-    public function hasCookie(string $name, $value = null, string $prefix = ''): bool
-    {
-        return array_key_exists($name, $_COOKIE);
-    }
-
-    //--------------------------------------------------------------------
-
-    public function deleteCookie
-    (
-        $name,
-        string $domain = '',
-        string $path   = '/',
-        string $prefix = ''
-    )
-    {
-        $COOKIE[$name] = null;
-        unset($COOKIE[$name]);
-
-        //set_cookie($name, '', '', $domain, $path, $prefix);
-    }
+	/**
+	 * If true, will not write output. Useful during testing.
+	 *
+	 * @var bool
+	 */
+	protected $pretend = true;
 
 }
diff --git a/tests/system/Helpers/CookieHelperTest.php b/tests/system/Helpers/CookieHelperTest.php
index b8d75ad578e0..605685f62322 100755
--- a/tests/system/Helpers/CookieHelperTest.php
+++ b/tests/system/Helpers/CookieHelperTest.php
@@ -53,7 +53,7 @@ public function testSetCookieByArrayParameters()
             'expire' => $this->expire
         ];
         set_cookie($cookieAttr);
- 
+
         $this->assertTrue($this->response->hasCookie($this->name, $this->value));
 
         delete_cookie($this->name);
@@ -84,12 +84,15 @@ public function testSetCookieSecured()
 
     public function testDeleteCookie()
     {
-        set_cookie($this->name, $this->value, $this->expire);
-        //$this->response->setCookie($this->name, $this->value, $this->expire);
+        $this->response->setCookie($this->name, $this->value, $this->expire);
 
         delete_cookie($this->name);
 
-        $this->assertEmpty($this->response->getCookie($this->name));
+        $cookie = $this->response->getCookie($this->name);
+
+        // The cookie is set to be cleared when the request is sent....
+        $this->assertEquals('', $cookie['value']);
+        $this->assertEquals('', $cookie['expires']);
     }
 
     //--------------------------------------------------------------------