Preheat oven to 400°F.
Heat oil in a large stainless steel skillet over medium-high until wisps of smoke form, 2 to 3 minutes.
Carefully add carrots in a single layer; cook, tossing occasionally, until golden brown in spots, 3 to 5 minutes.
Add butter, thyme, and garlic; cook, tossing constantly, until butter melts, about 30 seconds.
Sprinkle carrots with salt, and toss.
Transfer skillet to preheated oven.
Roast until carrots are fork tender, 8 to 10 minutes.
If desired, turn oven off, and crack oven door open; keep carrots warm in oven up to 15 minutes.
