This dish is meant to be one component of a larger Ethiopian meal. Serve with the Braised Cabbage, Carrots and Potatoes, Red Lentils (Misr Wat), Braised Beef with Peppers (Zilzil Tibs) and Quick Injera, layering the injera on a platter and mounding a portion of each dish on top. Tear off pieces of the injera to use as a "utensil" for scooping up bites of each.
4. Grind the toasted spices in a spice grinder to a fine powder. Add to the chile powder mixture and whisk to combine. Sift the spice mixture onto a piece of parchment paper, return to the bowl and whisk again. Return the pieces left in the sifter to the spice grinder and grind again as finely as possible; whisk into the spice mixture. Set aside.
5. To finish the niter kibbeh: Line a strainer with dampened cheesecloth. Skim the foam from the top of the butter and discard. Ladle the butter through the strainer, leaving behind the milk solids on the bottom of the pan.
7. While the chicken is marinating, prepare a bowl with ice water. Bring a medium saucepan of water to a boil and salt generously, making sure there is enough water to cover the eggs by 1 inch. Carefully add the eggs, bring back to a gentle boil and cook for 6 minutes. Transfer the eggs to the ice water, and shake or tap gently to crack the shells. Remove the eggs from the water and, when cool to the touch, peel. Set aside; do not refrigerate or they will not warm up in the sauce.
8. Put the onions in a large skillet over medium heat. Cook, stirring constantly, until golden, about 10 minutes, taking care not to burn them. You may need to reduce the heat as the onions dry out.
9. Increase the heat to medium high; add 1/3 cup of the niter kibbeh, 1/4 cup of the berbere, the garlic, ginger, tomato paste and black pepper, and cook, stirring, for 1 minute. Add the chicken, turning to coat well with the butter mixture, and then leave the chicken skin-side down in the pan.
10. Add the chicken stock, bring to a simmer, cover, reduce the heat to low and cook at a gentle simmer until the chicken is very tender, about 40 minutes. Remove the lid, increase the heat to medium and simmer, stirring occasionally, until the liquid is reduced and the sauce is very thick, about 45 minutes, occasionally spooning the sauce over the chicken.
11. Remove the pan with the chicken from the heat and add the eggs, turning to coat them in the sauce. Cover the pan and let rest for 5 minutes.
12. To serve, place the chicken thighs and eggs on injera or serving plates, and spoon the sauce over.
This recipe makes more than enough berbere and niter kibbeh to make the chicken. Refrigerate any leftovers to use in other Ethiopian recipes.