Pre heat oven to 200c.
Line a baking tray with a sheet or two of paper towel and set aside.
Boil chat potatoes until tender (usually 18 - 20 minutes), then drain.
Tip drained potatoes onto the lined baking tray. Using a potato masher, press down on each potato once - just firmly enough to crack open the potato slightly and allow steam to escape.
Place the salted butter in a small bowl and melt in the microwave. Then add garlic powder and salt to taste and mix to combine.
Remove the paper towel from under the potatoes, drying any excess moisture from the tray as you go. Space them out on the tray so that when they are crushed they don't touch each other.
Crush each potato a bit further to create more cracks and crevices (see my notes) and allow them to steam dry again for 5 minutes.
Brush potatoes with melted butter mixture.
Bake for 50 - 60 minutes (don't flip them) or until potatoes are browned and crisp.
Serve immediately, sprinkled with extra salt to serve if you like.