Place the millet in a small pot and add two cups of water. Cover with a lid and bring to a boil, once it's boiling lower the heat and let simmer for about 15 minutes or until all the water has evaporated.
In a large pan, sweat the onions, garlic, chillies with 2 tablespoons of olive oil for about 3 minutes.
Add the minced beef and cook until it is no longer pink. Now, mix in the tomatoes as well.
Slightly whisk the eggs, add them with all the remaining ingredients except for the bell peppers to the pan and stir well.
Fill the mixture into the bell pepper halves and place them in a greased oven dish. Bake at 350 °F/175 °C for 40 minutes or until tender. Depending on your oven you might need to cover the oven dish with tin foil.
In general, try to avoid the use of aluminium foil for health and environmental reasons but if it can't be avoided line it with a layer of parchment paper so that it won't be in direct contact with the food.