Heat the vegetable oil in a large pot over medium heat. Add the diced onion and cook until it softens, about 5 minutes.
Stir in the minced garlic and grated ginger. Cook for 1 minute until fragrant.
Add the berbere seasoning and stir for 30 seconds to toast the spices.
Add the rinsed red lentils, diced potatoes, crushed tomatoes, vegetable broth, and salt. Stir everything together.
Bring the mixture to a boil, then reduce the heat to low. Cover and simmer for 25 to 30 minutes, stirring occasionally, until the lentils and potatoes are tender.
Taste and adjust salt if needed. Ladle into bowls and top with chopped fresh cilantro before serving.