Grandma's wartime recipe is this, but instead of ketchup you add canned concentrated tomato and equal amounts of water (just full the can once with water again, helps to get the last bit out) and that's it. We call it red spaghetti, I make it for my kids from time to time, but this variation:
Grandma also added meatballs. Bake the small meatballs in a saucepan and when they're done, do the tomato thing in that pan, stir well, then add to spaghetti. Can't lose the grease, amirite...
i once had a long article in a pre-internet punk 'zine about the different meals you can make with free food like condiments.. salt pepper water ketchup mustard relish honey etc. it also taught how to use toothpaste as hair gel.
Edit: 20 minutes and I don't think I'm any closer to finding it. I told my partner what I was doing and they said 'oh that's gonna be hard!" I'm stubborn, so I may keep trying
I don't like ketchup like that. Fries, sure. Burger? A little. This? This is fucking gross. I also knew someone that put it on their pizza. On the inverse, I can eat yellow mustard straight
Pasta and ketchup is a common meal in Paris according to the one French Netflix show I watched where they ate it and never commented about how absurd it is.