Chili....doesn't get cheaper or easier than that!
Spaghetti...boring, yeah, but everyone likes it. I've seen a recipe where you add red lentils to the sauce to "beef it up" (ha!) and I want to try that.
Love making burritos with refried beans.
Vegetable soup with lentils and biscuits.
Mexican pizza (refried beans and salsa mixed to make the "sauce", add whatever toppings you want, bake, then add shredded lettuce). This is our new favorite. I've been making it about once a week. All the supplies are expensive if you don't make any of it from scratch, but even if you buy canned beans and salsa, you only use half and stick the rest in the fridge for later. If you make your dough and buy cheap ingredients, it can come to as little as $4 per pizza (feeds 2 very hungry people or 3-4 normal hungry people

).
Black bean burgers are SO much cheaper than boca burgers.
For the kids: Corn bread muffins with veggie dogs cut up and buried in the muffins. I can't find veggie corn dogs *anywhere* here and corn dogs are DS's favorite food right now. This is my compromise. I can make 6 muffins (2-3 dogs) for like $2 and there's plenty for the 2 of us.