Preheat the oven to 375°F (190°C) and line a baking dish or sheet pan with parchment paper for easy cleanup.

Wash the zucchini thoroughly, slice each one lengthwise, and use a spoon to scoop out the center to create boat shapes while leaving enough flesh around the edges so they hold their structure.

Lightly brush the zucchini halves with olive oil and sprinkle them with a pinch of salt and pepper, then place them cut-side up in the baking dish.

Bake the zucchini for about 10 minutes until they begin to soften slightly but still hold their shape.

Heat a large skillet over medium heat and add olive oil, then cook the diced onion for 3–4 minutes until softened and fragrant.

Add minced garlic and cook for about 30 seconds, stirring constantly so it does not burn.

Add the ground beef to the skillet and cook while breaking it apart with a spoon until browned and fully cooked.

Stir in taco seasoning and tomato paste, mixing well so the meat becomes evenly coated with the spices.

Remove the zucchini boats from the oven and spoon the taco meat filling evenly into each one.

Sprinkle shredded cheddar cheese generously over the top of the filled zucchini boats.

Return the baking dish to the oven and bake for another 10–12 minutes until the cheese is melted and bubbly.

Remove from the oven and garnish with avocado slices, chopped cilantro, or Greek yogurt if desired.

Serve warm and enjoy the bold taco flavors combined with tender zucchini and high-protein filling.