In 12-inch nonstick skillet, heat oil over medium-high heat. Cook potatoes and onions in oil about 5 minutes, turning potatoes constantly for even cooking, until oil begins to simmer; add thyme, salt and pepper. Simmer about 10 minutes longer, turning potatoes constantly, until potatoes are soft and tender. (If potatoes begin to fry and turn brown during cooking, reduce heat.) Remove from heat; drain (do not wash skillet). Place potato mixture in medium bowl; cool slightly.