Generously salt and pepper the foie gras lobes. Place them in a bowl with the Port wine to marinate. Cover and refrigerate for 8 hours.
Place the foie gras lobes in a terrine dish.
Preheat the oven to 80°C (176°F, gas mark 2-3).
Pour a shallow layer of water into an ovenproof dish and place the terrine in the center. Bake for 35 minutes in a water bath (bain-marie).
Allow the terrine to cool for a few minutes. Cover the foie gras with plastic wrap and place a weight on top to press it down into the terrine evenly. Ensure it is uniformly covered. Refrigerate for 12 hours.
Grill the slices of country bread in a toaster a few minutes before serving. Cut them into pieces about 1.2 inches thick. Wash the figs and cut them into thin slices.
Remove the foie gras from the terrine, discard the layer of fat that has formed on top, and cut thick slices (about 0.4 inches thick).
Place the foie gras on the toasts, sprinkle with a little fleur de sel, and top with a slice of fig. Serve immediately.