Preheat the oven to 350°F (180°C). In a deep baking dish or Dutch oven, arrange the peppers upright so that they fit snugly and won’t topple over.

In a large sauté pan, heat 1 teaspoon of olive oil over high heat. Add the ground beef and cook, stirring constantly, until the meat is just cooked. Drain the fat from the meat and set the meat aside.

In the same pan, heat 2 tablespoons of olive oil over medium heat. Add the onions, rice, garlic, salt, black pepper, oregano, paprika, and tomato paste. Sauté, stirring, for 1 minute, just to toast the rice. Pour in the wine and bring to a simmer. Remove the pan from the heat and stir in the meat, parsley, and 1 cup (240 ml) of the boiling water.

Loosely fill each pepper with the meat and rice mixture to just below the brim of the pepper. Gently press one slice of tomato on top of the opening of each pepper.

Pour ½ cup (120 ml) of the boiling water into the bottom of the baking dish. Tightly cover the dish with a lid or aluminium foil and bake for 30 minutes.

Remove the lid or foil and bake for an additional 30 minutes, until the peppers are tender and the rice is cooked.