In Spanish cuisine, pisto served as a tapa is most closely comparable to ratatouille. It is a cooked vegetable dish usually built from tomato, onion, zucchini, and pepper, with regional variations.
Pisto is especially associated with central and southern Spain, including La Mancha. The vegetables are cooked slowly in olive oil so their flavors meld. It may be served warm or at room temperature and can appear as a tapa, side dish, or accompaniment.
The comparison with ratatouille is useful because both are slow-cooked Mediterranean vegetable dishes, but they are not identical recipes. Pisto often emphasizes tomato and may be topped with a fried egg. Some versions also contain eggplant, while others use a different balance of vegetables.