Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper.

Cut each zucchini in half lengthwise. Using a spoon, scoop out the center flesh to create a hollow boat shape, leaving a 1/4-inch thick shell.

Lightly brush the cut sides and hollow interiors with olive oil. Arrange the zucchini halves cut-side up on the prepared baking sheet.

Pre-bake the zucchini boats for 5 to 7 minutes, until slightly softened but still firm.

While the zucchini pre-bakes, heat a large skillet over medium heat. Add the diced onion and cook, stirring occasionally, until translucent (about 4 minutes).

Stir in the minced garlic and cook for 30 seconds until fragrant.

Add the ground beef to the skillet. Cook, breaking it apart with a wooden spoon, until browned (about 6 minutes). Drain off any excess fat.

Pour in the tomato sauce, then season with Italian seasoning, smoked paprika, salt, and pepper. Stir well and let the mixture simmer for 5 minutes to meld the flavors.

Evenly spoon the beef filling into each pre-baked zucchini boat, pressing gently to fill the cavity.

Sprinkle shredded cheese over the top of each filled zucchini.

Return the baking sheet to the oven and bake for 15 minutes, until the cheese is melted and bubbly and the zucchini is tender.

Remove from the oven and let rest for 2 minutes. Garnish with fresh basil or parsley if desired.

Serve warm alongside a simple green salad or roasted vegetables.