Steam all veggies until tender for about 15 minutes.
Arrange vegetables and apples around edge of large platter.
Cut up bread into 1 - 1/5" pieces so it's easy to dip in the fondue.
Toss cheese with flour in large bowl.
Bring 3/4 cup beer, juice concentrate and mustard to simmer in large saucepan over medium heat.
Gradually add cheese.
Stir constantly until cheese is smooth and melted. Add more stout to thin out if needed.
Season to taste with salt and pepper.
Transfer to fondue pot. Serve and enjoy!