Preheat the oven to 375°F (190°C).
Cut the tops off the tomatoes and scoop out the seeds and pulp with a spoon, leaving a shell. Discard the seeds and pulp or reserve for another use.
4 large tomato
Place the hollowed-out tomatoes in a baking dish lined with parchment paper.
In a large skillet, heat the olive oil over medium heat. Add the onion and garlic, and sauté until softened, about 3-4 minutes.
1 tbsp olive oil, 1 small onion, 2 cloves garlic
Add the cumin, chili powder, and ground beef to the skillet, breaking it up with a spoon. Cook until browned and cooked through, about 5-7 minutes.
1 tsp cumin, 1 tsp chili powder, ½ lb beef
Stir in the black beans, and corn. Cook for another 2-3 minutes, until heated through.
½ cup black beans, ½ cup corn
Spoon the taco mixture into the hollowed-out tomatoes, dividing it evenly among them.
Bake in the preheated oven for 15 minutes. Top with shredded cheese and bake for an additional 5 minutes. Remove from the oven and let cool for a few minutes.
½ cup cheddar cheese
Serve with optional toppings such as chopped Greek yogurt, shredded lettuce, or chopped cilantro.
Greek yogurt, lettuce, cilantro