I love lentils. They might be my favorite pulse. They're kinda boring if you don't spice them up, but of course you will spice them up.
Here's an easy, and amazingly cheap dish I make when I am feeling lazy.
Extra step for the adventurous! Sautee some onions and garlic with some curry powder and/or chili powder. Extra optional: add green peppers, or any other handy veggies. Frozen peas, carrots, whatever's handy!
In a pot, boil some water and add chicken stock. Don't worry about how much water you add, you'll almost certainly need to add more. Add 1/2 to 3/4 of a cup (each) of rice and lentils to the garlic/onions/etc. This makes a fair amount of food! Add hot sauce if you want... tomato sauce, tomato paste, canned chopped tomatoes (etc) also make a great addition.
Keep the pot on a steady simmer for a while. You'll need to keep stirring, and making sure that it doesn't burn at the bottom. It takes 30-45 minutes. Avoid adding salt until the end, as extra salt slows down the speed of the lentils cooking. You know it's done when the texture is right-- pull out a little bit, and taste it. If it's too tough, add a bit more water and keep going. It's low mainenance, but not quite where you can ignore it. I try to keep the liquid level a little above the mixture while it's cooking, at least until the last 10 minutes.
After that, you can throw in whatever other seasonings you want. Even serve it with some meat, or whatever else is handy.
Easy, nutritious (mm, fiber!) and so cheap.