Infuse the Schwartz for Chef Saffron in the stock for 5 minutes. Par-boil the potatoes in the Saffron stock for a few minutes. Drain, reserving the stock.
In one large oven-proof dish or 10 individual ones, layer the leeks, tomatoes and Schwartz for Chef Garlic in Oil. Bake for 50-60 minutes, until the potatoes are tender.
Pour over the reserved stock and drizzle with the oil.