Make the mekelesha spice blend: In a dry skillet over medium-low heat, toast the cardamom pods until fragrant. Crack open the pods with the back of a knife, the bottom of a solid glass, a mortar and pestle or just your fingers and remove the seeds. Grind the cardamom seeds in a mortar and pestle or spice grinder. You will need 1/2 teaspoon of the ground spice.
In a small bowl, blend the cardamom, cinnamon, cloves and black pepper. You’ll need only 1/2 teaspoon for this recipe. (Store the rest in a cool, dry place for future misir wot batches or other stews and curries.)
Make the lentils: Place the lentils in a large bowl or colander, and pick over and discard any debris. Rinse the lentils until the water runs mostly clear (a little cloudy is okay, but you’ll see it turn from almost white to much more transparent as you go).
In a 12-inch nonstick skillet over medium-low heat, warm the oil. You may see a little rippling, but not much since the pan won’t get too hot. Add the onions and cook, stirring occasionally, until soft and translucent, about 10 minutes. Add the garlic and ginger and cook, stirring constantly, until aromatic, about 1 minute. Stir in the berbere and nigella along with a splash of water. Cover the skillet, reduce the heat to low and cook for 10 minutes. Uncover, stir, add another splash of water and cook for 5 minutes. Repeat the process every 5 minutes until the onions have cooked for a total of 25 to 30 minutes (no need to add more water at the end unless it’s looking very dry). Don’t rush the process or crank up the heat: The goal is to get the onions very soft and cooked down to almost a paste, as well as rounding out the berbere flavor and darkening its color.
Stir in the lentils, 2 cups of water and 1 teaspoon of salt. Increase the heat to medium-high and bring the mixture just to a boil. Reduce the heat to medium, or as needed, to maintain a gentle simmer. Stir occasionally, adding water as you go along to ensure the lentils cook through and the dish doesn’t dry out. You should use about 3 cups of water total. If you prefer a soupier stew, use more. Cook until the lentils are tender but not mushy, with just a bit of bite, 10 to 12 minutes, stirring in the 1/2 teaspoon of the mekelesha when they’re almost done. You can choose to cook the lentils longer, or gently mash them, if you want them broken down more. Taste, and season with more salt, if desired.
Remove from the heat. The misir wot is ready to serve, but will be better if refrigerated overnight, then reheated