In a large cast iron skillet or Dutch oven, place the water and the elbow macaroni. Cook until the noodles are done - you may have to add more water. Make sure to stir so that it doesn't stick to the bottom of the pan. You can cook this over the fire or a grill.
When the noodles are done the water should be evaporated ( if not, pour it off) and you can mix in the cans of chili. Heat up again.
When the chili is heated through, sprinkle the cheese on top.
Return to the fire/grill to melt the cheese.
The amount of water you need will vary, (evaporation rate, brand of noodles will all make this vary) so start with 5 and add 1/2 cup at a time afterwards until the noodles are cooked.