heat oil in a medium to large skillet. Add chopped onions and saute for 2-3 minutes. Then add in diced tomatoes and cook until it reduces into a thick sauce.
Add a little more canola oil and continue to fry for about 2 minutes. Blend fresh herbs,remaining half of onion, garlic and ginger with about a quarter cup of water. Add into skillet and simmer for about 5 minutes, stirring occasionally. Season with some salt
Add cooked beans, and another cup of water. Cover and simmer for about 10-15 minutes. ( Stir to prevent sticking and add more water if too thick). Season to taste and serve with rice ( or sweet potatoes/plantains..)