Heat oven to 425° F.
On a rimmed baking sheet, toss the potatoes, oil, thyme, salt, and pepper. Roast, tossing once, until the potatoes are tender, 20 to 25 minutes.
Meanwhile, cook the ravioli according to the package directions. Reserve ⅓ cup of the pasta water, drain the ravioli, and return them to the pot.
Gently mix the ravioli with the goat cheese and the reserved pasta water; fold in the sweet potatoes and sprinkle with more goat cheese, if desired.