Preheat your oven to 200°C (400°F) and line a baking sheet with foil.
Using a sharp paring knife, cut the tops off each bell pepper about a quarter inch from the stem, creating a lid. Carefully scoop out all seeds and membranes with a large spoon or melon baller, keeping the shape intact.
Carve simple spooky faces into the peppers—two triangles for eyes and a jagged smile—giving each a playful, goofy expression. Set aside the lids for later.
Heat olive oil in a skillet over medium heat. Add diced onions and minced garlic, sautéing until fragrant and translucent, about 3 minutes. The kitchen fills with a savory aroma, and the onions turn a light golden.
Add the ground meat to the skillet, breaking it apart with a spoon. Cook until browned and cooked through, about 5-7 minutes. Sprinkle in paprika, cumin, chili powder, and stir to combine. Cook for another 2 minutes, letting the spices coat the meat evenly.
Mix in the cooked rice and half of the shredded cheese, stirring until well combined. The filling should be moist, flavorful, and slightly sticky, with a fragrant spice aroma.
Use a spoon to generously stuff each hollowed-out pepper with the meat and rice filling, pressing down lightly to pack it in. Top each filled pepper with a generous sprinkle of shredded cheese.
Place the stuffed peppers on the prepared baking sheet. Cover loosely with foil to prevent over-browning, or leave uncovered if you prefer a crispy top.
Roast in the oven for 30-35 minutes, until the peppers are tender when pierced with a fork and the cheese is bubbling and golden.
Remove from the oven, let rest for 5 minutes. Optionally, replace the pepper lids for a full pumpkin look. Garnish with additional shredded cheese if desired and serve warm.