Flutter Dart Error parsing DateTime from Cloud_Firestore

Question

I'm trying to Sort the Date i get from Cloud_Firestore and adding the WeekDay so that the upcoming Date is at the Top and then the Dates more in the Future get behind. Trying this with DateTime.parse i get following Error seen below. I Store only the Date without the WeekDay in Cloud_Firestore.

Can I get the WeekDay just from Parsing or do i need to Store it with the Date?

Error

Invalid date format
21-05-2020
The relevant error-causing widget was
    StreamBuilder<QuerySnapshot> 
lib/…/MealPlan/mealTile.dart:90
════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════
Invalid date format
21-05-2020
The relevant error-causing widget was
    StreamBuilder<QuerySnapshot> 
lib/…/MealPlan/mealTile.dart:90
════════════════════════════════════════════════════════════════════════════════

Code

import 'package:flutter/material.dart';
import 'package:mealapp/models/Widgets/whenAndWhatToEat.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:intl/intl.dart';
import 'package:mealapp/models/global.dart';

class MealTile extends StatefulWidget {
  final MealsAndWhen mealsAndWhen;
  MealTile({this.mealsAndWhen});

  @override
  MealTileState createState() {
    return MealTileState();
  }
}

class MealTileState extends State<MealTile> {
  String id;
  final db = Firestore.instance;
  String meal;

  Widget buildItem(DocumentSnapshot doc) {
    DateTime now = doc.data['Date'].toDate();
    DateFormat formatter = DateFormat('dd-MM-yyyy');
    String formatted = formatter.format(now);
    DateTime parsedDate = DateTime.parse(formatted);
    String date = formatted;

    return Container(
      margin: const EdgeInsets.all(8.0),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.center,
        children: <Widget>[
          Text(
            'Meal:',
            style: TextStyle(
                fontSize: 24, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          Text(
            '${doc.data['Meal']}',
            style: TextStyle(
                fontSize: 24, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          SizedBox(height: 20),
          Text(
            'When:',
            style: TextStyle(
                fontSize: 20, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          Text(
            date,
            style: TextStyle(
                fontSize: 20, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          Row(
            mainAxisAlignment: MainAxisAlignment.end,
            children: <Widget>[
              SizedBox(width: 8),
              FlatButton(
                onPressed: () => deleteData(doc),
                child: Row(children: <Widget>[
                  Text('Delete',
                      style: TextStyle(
                          fontWeight: FontWeight.bold, color: Colors.white)),
                  Icon(Icons.delete_forever, color: Colors.white),
                ]),
              ),
            ],
          ),
        ],
      ),
      decoration: BoxDecoration(
        color: lightBlueColor,
        borderRadius: BorderRadius.all(Radius.circular(12)),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: darkGreyColor,
      body: ListView(
        padding: EdgeInsets.only(top: 220),
        children: <Widget>[
          StreamBuilder<QuerySnapshot>(
            stream: db.collection('mealList').snapshots(),
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return Column(
                    children: snapshot.data.documents
                        .map((doc) => buildItem(doc))
                        .toList());
              } else {
                return SizedBox();
              }
            },
          ),
        ],
      ),
    );
  }

  void deleteData(DocumentSnapshot doc) async {
    await db.collection('mealList').document(doc.documentID).delete();
    setState(() => id = null);
  }
}

MealTile.dart

import 'package:flutter/material.dart';
import 'package:mealapp/models/Widgets/whenAndWhatToEat.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:intl/intl.dart';
import 'package:mealapp/models/global.dart';

class MealTile extends StatefulWidget {
  final MealsAndWhen mealsAndWhen;
  MealTile({this.mealsAndWhen});

  @override
  MealTileState createState() {
    return MealTileState();
  }
}

class MealTileState extends State<MealTile> {
  String id;
  final db = Firestore.instance;
  String meal;

  Widget buildItem(DocumentSnapshot doc) {
    DateTime now = doc.data['Date'].toDate();
    DateFormat formatter = DateFormat('dd-MM-yyyy');
    String formatted = formatter.format(now);

    return Container(
      margin: const EdgeInsets.all(8.0),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.center,
        children: <Widget>[
          Text(
            'Meal:',
            style: TextStyle(
                fontSize: 24, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          Text(
            '${doc.data['Meal']}',
            style: TextStyle(
                fontSize: 24, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          SizedBox(height: 20),
          Text(
            'When:',
            style: TextStyle(
                fontSize: 20, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          Text(
            formatted,
            style: TextStyle(
                fontSize: 20, fontWeight: FontWeight.bold, color: Colors.white),
            textAlign: TextAlign.center,
          ),
          Row(
            mainAxisAlignment: MainAxisAlignment.end,
            children: <Widget>[
              SizedBox(width: 8),
              FlatButton(
                onPressed: () => deleteData(doc),
                child: Row(children: <Widget>[
                  Text('Delete',
                      style: TextStyle(
                          fontWeight: FontWeight.bold, color: Colors.white)),
                  Icon(Icons.delete_forever, color: Colors.white),
                ]),
              ),
            ],
          ),
        ],
      ),
      decoration: BoxDecoration(
        color: lightBlueColor,
        borderRadius: BorderRadius.all(Radius.circular(12)),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: darkGreyColor,
      body: ListView(
        padding: EdgeInsets.only(top: 220),
        children: <Widget>[
          StreamBuilder<QuerySnapshot>(
            stream: db.collection('mealList').snapshots(),
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return Column(
                    children: snapshot.data.documents
                        .map((doc) => buildItem(doc))
                        .toList());
              } else {
                return SizedBox();
              }
            },
          ),
        ],
      ),
    );
  }

  void deleteData(DocumentSnapshot doc) async {
    await db.collection('mealList').document(doc.documentID).delete();
    setState(() => id = null);
  }
}