"This is a great potato casserole for the grill. Clean up can't get any easier than just tossing the foil! These can also be baked in a 350 degree oven if space on the grill is at a premium. Don't be tempted to skip the celery seed, it's what makes these unique."
Melt butter in a medium saucepan. Blend in flour, salt, seasoned pepper and celery seed. Cook for one minute. Stir in milk and cook over medium heat until thickened and bubbly. Cook and stir for one minute longer.
Add potatoes, onion and green pepper and gently combine.
Turn potato mixture out onto a large sheet of heavy duty foil. Sprinkle with paprika. Fold foil loosely around potato mixture and seal tightly.
Grill on covered grill about 45-50 minutes, until potatoes are tender, turning them every 15 minutes.