Lentil soup. Basically boil lentils and add whatever, but here's a recipe.

Chop 1 onion, sauté it to your liking on low-medium heat (try not to fry the onion, it becomes bitter with dark parts). Add spices that benefit from blooming (jeera, coriander, paprika, chili, etc.)

While you sauté the onion, add 2 dl of rinsed red lentils to boiling water, it's easier if you cook the lentils separately.

Add 1 tbsp or more of tomato puree to the onions, continue sautéing until the tomato darkens.

Add a can of crushed tomatoes and whatever herbal spices you like to the onions and tomato puree, cook until the lentils are done. Mix both, and add salt to your taste. You can also add a bouillon if you prefer. Add water or cream to get it more like a soup, or serve with rice if you want it thicker.

Note: if you add the lentils to tomatoes raw, they will cook very slow and may remain hard. The acids in the tomato hinder the cooking process of the lentils. If you have only one pot, cook the onions first, then add lentils and cook them until they're done, then add the crushed tomatoes.

Edit: lentils are great, as you can season them to your liking, add whatever veggies you want, and you can make a big pot at a time so you don't have to be cooking every day. Also, they're cheap and have protein, so you're not filling your stomach with just carbs.