Carmona eats well and cheaply compared to Seville. The old town has a handful of good restaurants clustered around the main squares; the Parador also has a restaurant that is open to non-guests.
Bar-Restaurante El Tapeo de Carmona — Calle Santa Ana. A reliable local spot for tapas and raciones in the old town. The jamón and the local cheeses are both worth ordering.
Restaurante Goya — near the Puerta de Sevilla. Traditional Andalucian cooking in a no-frills dining room. The menú del día at lunchtime is excellent value.
Parador de Carmona — if you are going to splurge, the Parador restaurant uses local produce and has the best views in Carmona from its terrace. The gazpacho and the pork dishes are the things to order.