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

Wash zucchinis, slice them in half lengthwise, scoop out seeds and flesh, brush with olive oil, and sprinkle with salt and pepper. Arrange cut-side up on a baking sheet.

In a large skillet, heat olive oil. Add diced onion and sauté until translucent, about 3-4 minutes, then add minced garlic for another minute.

Stir in ground beef, cooking until browned and no longer pink, about 5-7 minutes.

Mix in diced bell pepper and cook for 2-3 minutes. Stir in tomato sauce and Italian seasoning, simmer for 5 minutes.

Spoon the filling into hollowed zucchini halves, top with shredded cheese.

Bake in preheated oven for 25-30 minutes or until zucchini is tender and cheese is golden.

Remove from oven, let cool for a few minutes before serving warm.