While the way you are doing your coffee sounds like a good way, let me give you another option for cooking your meals on the road. Recently we were out in South Dakota riding around in our Model T's and we knew we would be hungry after visiting Mt. Rushmore. With four cars in our group that each had 'manifold cookers', we cooked lunch for about 16 people. One cooker was filled with BBQ Pork and Rice, another had Bratwurst, Sour Kraut & Potatoes, in our red 1916 Touring we had Polish Sausages with Peppers & Onions, and in our '26 pick-up truck that James Rogers was driving, we had Smoked Sausages with the fixin's.
Before we left the hotel that morning, the ladies all went grocery shopping and fixed the cookers. We had about a 1½ hour, 40 mile jaunt over to Mt. Rushmore and then a hard pull up the mountain to the park entrance. As a precautionary measure, we stopped as we entered into the town of Keystone and checked the water level in each cooker. It was one of the best smells ever coming from under the hood as we were climbing to the top. Once parked in the parking lot, the food had a couple hours to finish cooking as the heat from the manifold slowly cooled, and when we left the park, everything got re-warmed as we came off the mountain and back through town.
Once through town, we found a park that had some picnic tables and we set up a smorgasboard where everyone sampled out of everyone's cooker, and ate until we were all stuffed. You can look at the pictures below and get an idea of what our meal looked like.
I might add that they make cookers for Model A manifolds too, or you could fabricate something yourself and put on the manifold. While we were up at Rushmore, there were several cars around us that had cooked hot dogs, meat loaf, and even a pineapple upside down cake that they were giving out samples. Everyone should give it a try sometime!!
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