Preheat oven to 375°F.
Using a spoon, hollow out the middle of each zucchini half, leaving enough intact around the edges so that the zucchini is still sturdy and retains its shape. Set the inside scraps aside for another use or discard. Place zucchini boats in a 9×13-inch baking dish.
Heat olive oil over medium heat in a large skillet. Once hot, add the ground beef and cook until browned, breaking up with a spatula.
Once browned, add the yellow onion, red bell pepper, and garlic. Stir to combine and cook for an additional 3 to 4 minutes until slightly softened.
Add the black beans, corn, and spices to the skillet and stir until well combined.
Add the salsa and half of the shredded cheese, mix until incorporated then turn off the heat.
Spoon an even amount of the mixture into each zucchini half and top with the remaining cheese.
Cover with aluminum foil and bake for 30 to 35 minutes. Remove foil for the last 5 minutes to fully melt the cheese.
Garnish with fresh cilantro and serve.
