Apparently, this is a thing. Not so much of a thing that it has a special name or origin story or anything, but enough that when you search for "tomato potato green bean recipe" you get a few pages of it.
There's some small variation between the recipes--ratios and cooking methods mostly. A few include sausage and since I'm having this as a main dish I included that. I saw one that roasted the tomatoes and I thought I might try expanding that aspect out a bit.
So I preheated my oven to 300 degrees and quartered my three remaining plum tomatoes, took out a baking sheet, poured in a bit of olive oil, added some fresh thyme and rosemary and kosher salt, added the tomatoes and tossed everything about a little and put it in the oven for an hour and a half.
Meanwhile I cut up my remaining potatoes into similar-sized pieces (mostly quartered too), boiled them in a big pot of salted water until tender--about 8 minutes but I think I overcooked them a little. I tossed them with a bit more olive oil, herbs and salt, and added them to the pan--cut side down--with an hour left on the clock.
Next, I simmered a half pound of green beans in the selfsame big pot of salted water until al dente. Those went onto the pan with a half hour left on the clock.
Finally, I fried a quarter pound of relatively-thinly-sliced keilbalsa until crisp. I'd roast that too, but I want something crisp and I can't count on the potatoes in that overcrowded pan. I think there's some leeway in the choice of sausage so long as the other seasonings match. I'd use Italian sausage if I wasn't out of fresh basil.
After the full hour and a half, I extracted the tomatoes from the pan and transferred them to a bowl. Into the food processor went a garlic clove, a couple Tablespoons of mayo, a teaspoon of red wine vinegar and a teaspoon of German mustard. While that was blending I drizzled in a Tablespoon of olive oil from the pan. I tried anyway, but I don't have one of those mini-processor bowl inserts so it didn't work out. After the garlic clove got minced I just mixed everything by hand. Once that was smooth I added the tomatoes and pulsed a few times until still slightly chunky and added salt and pepper (and more vinegar) to taste. [While the roasting process I came up with on my own, this distinctive dressing is pretty close to the one from the June 2003 issue of Food and Wine magazine.]
So how is it? Not bad, but it could use work. The potatoes would be improved by another half hour of roasting and the green beans don't gain anything by their half hour. I'd rather have them plump and crisp than withered. And the dressing is wrong--mayo plus tomatoes plus vinegar equals French dressing. It hides the nice roasting the tomatoes got, too. Next time, I'll leave those whole and just dress it with a little vinegar added to the olive oil left in the pan.
I think this all might be better cold. I'll try the leftovers again tomorrow and let you know in the wrap-up.