Preheat the oven to 350 degrees F.
Place the tomatoes still on the vines (plus any that fall off the vines) on a sheet pan. Rub or brush gently with olive oil and sprinkle generously with kosher salt and pepper.
Roast for 10 to 15 minutes, until the tomatoes are tender and a few start to split. Sprinkle with basil, if using, and fleur de sel, and serve on the stem hot or warm.
"Cooking for Jeffrey" by Ina Garten © Clarkson Potter 2016. Provided courtesy of Ina Garten. All rights reserved.