Prepare a marinade with oil, aromatic herbs, paprika, pepper and sliced garlic. Add the tomato concentrate and mix well. Peel the potatoes and cut them into wedges. Cook them in boiling salted water for 5-6 minutes. Drain, leave to cool and mix evenly with the marinade. Transfer them to an oven dish, cover them with aluminium foil and bake in a preheated oven at 180°C for 20 min. Halfway through cooking, brush again with the marinade and remove the foil. Serve hot, sprinkled with lightly crushed salt and, to taste, a few rosemary leaves.