Prep the oven and pan. Preheat the oven to 400°F (200°C). Lightly grease a large baking dish or line it with parchment for easy cleanup.

Hollow the zucchini. Trim the ends and slice each zucchini in half lengthwise. Use a spoon to scoop out the centers, leaving a 1/4-inch border to form “boats.” Reserve about half of the scooped flesh, chop it, and set aside.

Par-bake the boats. Brush the zucchini halves with olive oil and sprinkle with a pinch of salt and pepper. Place them cut side up in the baking dish and bake for 10 minutes to soften slightly.

Brown the protein. While the zucchini bakes, heat a large skillet over medium heat. Add the ground turkey or beef and cook, breaking it up, until mostly browned. Drain excess fat if needed.

Sauté the veggies. Add the onion, garlic, and bell pepper to the skillet. Cook 3–4 minutes until softened. Stir in the chopped zucchini flesh and cook another 2 minutes to reduce moisture.

Season and simmer. Add taco seasoning, salsa, tomato paste (if using), black beans, and corn. Stir well and cook 3–5 minutes until thickened and fragrant. Taste and adjust salt and pepper. The mixture should be saucy but not watery.

Fill the boats. Spoon the taco mixture into each par-baked zucchini, mounding it slightly. Press lightly so it holds together.

Add cheese. Sprinkle shredded cheese evenly over the tops. Use more or less based on your preference.

Bake to finish. Return to the oven and bake 10–12 minutes, until the zucchini is tender and the cheese is melted and bubbly.

Garnish and serve. Let the boats rest for 3–5 minutes. Top with cilantro and your favorite add-ons like avocado, jalapeños, a dollop of Greek yogurt, and a squeeze of lime.