2. Soak some beans in a large container (some people recommend lightly grinding the beans first to make it easier to remove the skin) for about an hour or so.
3. Prepare foil or empty cans for the cooking:
4. If using empty cans, make sure their interior is clean, and lightly greased.
5. If using foil:
6. Tear off about 1 foot of the foil.
7. Fold the foil in half.
8. One of the edges is closed and fine. For two of the other edges, roll them a few times over to make sure they will take the weight of the mixture (at least an inch-worth of rolling).
9. When you are done, the foil will look like rectangles with only one edge open.
10. Rub the beans between your hands to peel the skin off. (The skin should float to the top of the container.) Keep doing this until you have most of the skin off the beans.
11. Grind the beans into a smooth, finely-ground, mostly-liquid paste.
12. Add blended tomatoes (or tomato sauce and paste), oil (just a few teaspoons), a little salt, and if you wish, you can also add hard-boiled eggs, or dried fish, or meat, or ground beef.
13. Place into either the foil or the cans.
14. If using cans, simply pour some of the batter into the cans, making sure you leave enough room for the cooking moin moin to rise.
15. If using foil, pour some of the batter into the foil, and then close up the last edge of the foil (once again, by rolling it securely).
16. Place some water in a large pot.
17. Place the cans or the foil into them.
18. Boil the moin moin until it forms a solid substance (at least half an hour)
19. Remove them from the cans or the foil before serving.
20. Usually eaten with rice, meat, and maybe other sides.