Peel and slice Yukon Gold potatoes into 1-inch thick rounds. Place them in cold, salted water and bring to a gentle boil for 8-10 minutes until just tender. Drain and cool.

Melt 2 tablespoons of unsalted butter and add 1 tablespoon of olive oil in a large skillet over medium heat. Add onions and a pinch of salt and sauté for 5-7 minutes until soft and golden. Stir in garlic and thyme and cook for an additional minute.

Gently add drained potato slices to the skillet and cook on one side for 6-8 minutes without moving. Flip carefully and crisp the other side for another 6-8 minutes. Adjust heat as necessary.

Season with sea salt and black pepper to taste. Remove from heat and sprinkle with chopped parsley. Serve immediately.