Most nights we do some variety of the same technique, especially if we're short on prep time.
Some sort of meat (chicken, pork chops, beef) cubed
Whatever veggies you like, cut into bite size pieces
Potatoes, sliced about 1/4 inch thick
Spread out a bit of foil, add all the food in a single layer, add a bit of seasoning and some oil to prevent sticking. Fold up the sides into a little packet, double wrap if you think you need it. Give it 20 or 30 minutes and it's ready to eat.
It's an easy one to mix up a little - pork chops with cranberries (mixed with sugar!) is good. Chicken with pineapple, brocc, pea pods on rice instead of potatoes is a good one too. You can do the meat and veggies separate if you think they need separate cook times.
It's simple, and I'm sure most do it already, but thought I'd add it in case someone hadn't figured this cooking method out yet.

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Cheers!