Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: see manufacturer). Lightly press 8 jacket potatoes in their skins with a masher (alternatively a spatula). Place on an oiled baking tray.
For the seasoning oil, mix 5 tablespoons of olive oil with garlic cloves, lemon juice, sea salt and chili flakes. Wash thyme and rosemary, shake dry and cut into pieces, add to the oil. Drizzle seasoning oil over the potatoes.
Bake the potatoes in a hot oven for about 10 minutes.