In a deep bowl, mix the olive oil, mustard, paprika, black pepper, rosemary, and salt until well combined.

Cut the potatoes into thick slices (without peeling them) and boil them in water for 5 minutes to remove some of the starch.

Drain the potatoes well and place them in the prepared marinade. Let them sit for 10 minutes to absorb the flavors.

Preheat your oven to 180°C (350°F).

Line a baking tray with parchment paper and spread the marinated potatoes on it.

Place the tray in the oven for 20 minutes, turning the potatoes occasionally to ensure they cook evenly.

Serve the potatoes hot.