In a large pot or saucepan, heat the oil. Brown the meat on all sides. Remove it and set aside.
In the same oil, sauté the chopped onion until soft (about 5 minutes). Add the tomato paste and cook for 2-3 minutes.
The key to a flavorful peanut sauce is using high-quality, unsweetened peanut butter and simmering it slowly to allow the peanut oil to separate and re-emulsify with the sauce, which adds depth. The meat should be simmered until tender. In Togo, vegetables such as sweet potatoes or pumpkin are sometimes added. For a vegetarian version, the meat can be replaced with tofu or more vegetables.
In a large pot or saucepan, heat the oil. Brown the meat on all sides. Remove it and set aside.
In the same oil, sauté the chopped onion until soft (about 5 minutes). Add the tomato paste and cook for 2-3 minutes.
Return the meat to the pot. Add the crushed tomatoes, broth, salt, pepper, bouillon, and the whole hot pepper (if using). Bring to a boil and simmer for 20 minutes.
Gradually stir the peanut butter into the sauce until it is fully dissolved and has a creamy texture. If the sauce is too thick, add a little more broth.
Reduce the heat to low and simmer for another 30 minutes. Stir the sauce occasionally to prevent the peanut butter from sticking to the bottom. The sauce is ready when it is thick and fat begins to separate on the surface.
Carefully remove the pepper. Serve the sauce hot, generously poured over the cooked white rice.