Place the potatoes and 2 tablespoons salt in a large saucepan and add enough water to cover the potatoes. Bring to a boil, reduce the heat, and simmer until potatoes are tender when pierced with a fork.
Drain potatoes and place on a sheet pan. Toss with 1 tbsp olive oil to coat, 1 tbsp salt and 1 tsp of pepper. Using a metal measuring cup, press each potato until flattened but mostly still in one piece..
Sprinkle with the cubes of butter, minced garlic and chopped thyme leaves, then drizzle the remaining olive oil over top.
Bake for 20-25 minutes until skins are nicely browned. Sprinkle with pinch of salt when hot and serve.