• Preheat oven to 375ºF. Brush tortillas on both sides with olive oil; bake on parchment paper–lined baking sheets, turning halfway through cooking, for 8 minutes. Let cool.
• Tomato Salsa: Meanwhile, mix together tomatoes, sweet onion, cilantro, jalapeño (if using), lime juice, salt and pepper.
• Spread each tortilla with 2 tsp pesto; arrange steak slices over top. Spoon salsa over top.

Tip: Sprinkle with a Mexican cheese, such as queso fresco or Cojita.