Prepare Ingredients: Chop onions, tomatoes, and mince garlic. Measure out Ethiopian chili powder, kororima, and shiro paste powder.
Sauté Onions and Garlic: Heat oil in a pan. Add chopped onions and garlic, sauté until translucent and fragrant.
Add Tomatoes and Spices: Add chopped tomatoes, Ethiopian chili powder, and kororima. Cook until tomatoes soften and spices release aroma.
Add Shiro Paste Powder: Gradually add shiro paste powder while stirring to avoid lumps. Add water as needed to achieve desired stew consistency.
Simmer and Finish: Simmer the mixture until thickened. Stir in vegetarian butter for richness. Adjust seasoning to taste.