Preheat and prep: Heat the oven to 400°F (200°C). Line a baking sheet or 9x13-inch baking dish with parchment for easy cleanup.
Hollow the zucchinis: Trim ends and slice each zucchini lengthwise.
Use a spoon to scoop out the center, creating “boats,” leaving about 1/4-inch walls. Reserve about half the chopped zucchini flesh and finely chop it.
Season the boats: Brush the hollowed zucchini with a little olive oil, and sprinkle with salt and pepper. Place cut-side up on the baking sheet.
Par-bake: Bake the zucchini boats for 8–10 minutes to soften slightly.
This helps them cook through without getting watery later.
Cook the filling aromatics: While the boats bake, heat 1 tablespoon olive oil in a large skillet over medium heat. Add diced onion and sauté 3–4 minutes until translucent. Stir in garlic for 30 seconds.
Brown the meat: Add ground turkey to the skillet.
Break it up and cook until no longer pink, about 5–6 minutes. Season with taco seasoning, chili powder, cumin, salt, and pepper.
Add zucchini and beans: Stir in the chopped zucchini flesh and black beans. Cook 2–3 minutes to soften the zucchini and warm the beans.
Create a saucy finish: Stir in tomato paste and broth.
Simmer 2–3 minutes until thick and glossy. Taste and adjust salt and spice.
Fill the boats: Spoon the hot filling into each par-baked zucchini boat, mounding slightly. Top with shredded cheese.
Bake to melt: Return to the oven for 8–10 minutes, until the cheese is melted and the zucchini is tender but not mushy.
Add fresh toppings: Finish with cilantro, salsa, avocado, jalapeños, a squeeze of lime, and a dollop of Greek yogurt if you like.
Serve: Enjoy warm.
Pair with a simple side salad, cauliflower rice, or tortilla chips if you want some crunch.