How to Make It
Heat oven to 400° F. Rub the potatoes with 1 teaspoon of the olive oil. Place on a rimmed baking sheet and bake, turning occasionally, until tender and easily pierced with a paring knife, 65 to 75 minutes.
Fifteen minutes before the potatoes are done, on a large rimmed baking sheet, toss the tomatoes and thyme with the remaining 1 tablespoon of oil, 1 teaspoon salt, and ¼ teaspoon pepper. Roast, tossing occasionally, until the tomatoes have burst, 12 to 15 minutes.
Split the potatoes and, dividing evenly, top with the ricotta and tomato mixture.