Wash and dry all produce. Core and dice tomatoes. Thinly slice scallions, keeping greens and whites separate. Drain corn. Halve lime. Toss beef, enchilada spice, and Southwest spice in a medium bowl. Season with salt and pepper. Slice jalapeño into thin rings, removing ribs and seeds for less heat.

Heat a large drizzle of olive oil in a large pan over medium-high heat. Add corn and scallion whites. Cook, tossing, until corn is lightly browned, 3-4 minutes. Season with salt and pepper. Transfer to another medium bowl. TIP: Rinse out pan if there’s anything stuck to the surface's.

Heat another large drizzle of olive oil in same pan over medium-high heat. Add beef in a single layer and cook without disturbing until it starts to brown, 1-2 minutes. Give it a toss and continue cooking to desired doneness, 1-2 minutes more. TIP: Work in batches to avoid overcrowding the pan.

Wrap tortillas in a damp paper towel and microwave on high until warm, about 30 seconds. TIP: Alternatively, wrap tortillas in foil and warm in oven for 5 minutes at 425 degrees.

Add tomatoes, scallion greens, and a squeeze of lime to the bowl with corn. Toss to combine. Season with salt and pepper.

Divide steak and salsa between tortillas. Dollop with sour cream. Tear cilantro leaves from stems and scatter over. Top with jalapeño (to taste—you may want to leave it out for the kids).