Preheat your broiler to high.

Chop the celery finely. Peel and cut the carrot in half. Chop the thyme leaves and remove the stems.

Fill a large saucepan halfway with water, season with salt, and bring to a boil. Place the potatoes in a saucepan.

Cook until the vegetables are tender, about 20 minutes.

When the potatoes are done, mash them with butter, thyme, and sour cream. Mash until the consistency is smooth.

Set aside and season with salt and pepper.

In a large skillet, heat some oil. Mix in the carrot, celery, and onion.

Season with salt and pepper after cooking until the vegetables are tender.

Cook for another minute after adding the garlic powder and thyme.

Place the beef on top of the vegetables, breaking it up.

Cook until the meat is golden brown. Ensure that both sides are cooked evenly.

Stir in the flour until thoroughly combined.

Combine tomato paste, water, and beef stock in a mixing bowl. Bring the mixture to a boil and cook until it thickens.

Top with the mashed potatoes.

Sprinkle with cheddar cheese.