<?php

namespace App\Http\Controllers;

use App\User;
use Illuminate\Http\Request;

class APIController extends Controller
{
    public function NoAPIResponse(Request $request){
        return response()->json([
            'message' => 'Api call is invalid'
        ])->setStatusCode(400)
            ->header('Content-Type', 'text/json');
    }

    public function currentUser(Request $request){
        $user = User::fullUser(auth()->id());
        if($user->email == env('APP_SUPER_ADMIN'))
            $user->superadmin = true;
        return response()->json();
    }
}

<?php

namespace App\Http\Controllers;

use App\User;
use Illuminate\Http\Request;

class APIController extends Controller
{
    public function NoAPIResponse(Request $request){
        return response()->json([
            'message' => 'Api call is invalid'
        ])->setStatusCode(400)
            ->header('Content-Type', 'text/json');
    }

    public function currentUser(Request $request){
        return response()->json(User::fullUser(auth()->id()));
    }
}

--- 
+++ 
@@ -15,6 +15,9 @@
     }
 
     public function currentUser(Request $request){
-        return response()->json(User::fullUser(auth()->id()));
+        $user = User::fullUser(auth()->id());
+        if($user->email == env('APP_SUPER_ADMIN'))
+            $user->superadmin = true;
+        return response()->json();
     }
 }
Add superadmin trait to user with superadmin email

