This simple side is a Mexican rendition of an Italian caprese salad.
Arrange tomatoes on a platter. Season with salt. Arrange avocado slices on top of tomatoes, dividing evenly. Squeeze lime juice over top. Crumble queso fresco over top. Top salad with cilantro leaves. Refrigerate, covered, until ready to serve (up to 1 hour). Season with salt and pepper, and drizzle with oil before serving.