Heat the vegetable oil in a large pot over medium heat.
Add the chopped onions and cook until soft and translucent, about 5 minutes.
Stir in the minced garlic and ginger, and cook for another 2 minutes until fragrant.
Stir in the tomato paste, ground cumin, ground coriander, ground turmeric, paprika, and berbere spice mix (if using). Cook for 1-2 minutes.
Add the chicken pieces to the pot and cook until browned on all sides.
Add the diced tomatoes and water or chicken broth, stirring to combine. Bring to a boil.
Reduce heat to low and simmer for 30-40 minutes, or until the chicken is cooked through and tender.
Season with salt and black pepper to taste.
Garnish with fresh cilantro before serving.
Enjoy your meal!