In a heavy skillet, heat oil to medium-high. Season both sides of the steak slices with salt and pepper and brown on both sides for about 5 minutes per side.
Remove the steak slices and place them in a flat-bottom baking dish.
In the skillet with the drippings, add the chopped onion, diced carrots, sliced celery, and sliced garlic. Cook over medium heat until the vegetables begin to soften, about 10 minutes.
Increase heat to medium-high and add the bottle of red wine along with the thyme. Let the mixture reach a slow boil point and cook for 2-3 minutes.
Pour the cooked marinade over the steak slices, allow to cool, and then refrigerate overnight.