In a large pan or wok, heat the Niter Kibbeh over medium-high to high heat (or use Ghee if you don't have Kibbeh).
Add the beef. Sear it in a single layer so it fries quickly and doesn't begin to stew. Sear for 3–5 minutes until the meat is browned on all sides. Remove the meat from the pan and set aside.
If needed, add a little more Niter Kibbeh to the pan. Add the onion and bell pepper (if using) and sauté until the onion softens and begins to caramelize (about 5 minutes).
Add garlic, ginger, and Berbere spice. Sauté for 1–2 minutes until the aroma develops (be careful not to burn the Berbere).
Return the seared meat to the pan with the vegetables and spices.
Stir quickly to coat the meat in the sauce. Season with salt and black pepper. Sauté for another 1 minute until the flavours are combined. The sauce should be minimal; the meat should be drier and seared.