Preheat your oven at 200°C/392°F. Bring a pot of water to boil. Peel your potatoes, cut them into 1 cm cubes and place them in the boiling water. Leave them in the pot for 8 minutes.
Drain the water from the pot. Add the olive oil, the rosemary and the garlic. Season with the salt and pepper and stir everything really well, but gently, so you don't end up with mashed potatoes.
Put the potatoes in an oven proof dish and cook for about 1 hour. Once every 20 minutes stir the potatoes a bit.
When they have a beautiful golden crust they're ready.
Recipe by Simply yum at https://www.simplyum.com/rosemary-oven-cooked-potatoes/