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

Hollow the zucchini. Slice each zucchini in half lengthwise. Use a spoon to scoop out the centers, leaving about 1/4 inch of flesh to form a sturdy “boat.” Reserve about half of the scooped flesh, finely chop it, and set aside.

Par-bake the zucchini boats. Arrange the zucchini cut side up in the baking dish. Drizzle with a little olive oil and sprinkle with salt and pepper. Bake for 8–10 minutes to soften slightly while you make the filling.

Cook the aromatics. Heat a skillet over medium heat with a drizzle of olive oil. Add the diced onion and cook 3–4 minutes until translucent. Stir in the garlic and cook 30 seconds until fragrant.

Brown the meat. Add the ground beef (or turkey/chicken) to the skillet. Break it up with a spoon and cook until browned and no longer pink, about 5–7 minutes. If there’s excess grease, drain it.

Season and simmer. Stir in taco seasoning, tomato paste, diced tomatoes, and the chopped zucchini flesh. Add the broth or water. Simmer 3–4 minutes until thick and saucy. Taste and adjust salt and pepper.

Stuff the boats. Remove the par-baked zucchini from the oven. Spoon the taco filling into each boat, packing it in firmly. Top with shredded cheese.

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

Add toppings and serve. Let the boats rest 5 minutes. Add salsa, avocado, jalapeños, cilantro, and a dollop of sour cream. Finish with a squeeze of lime. Serve warm.