This from my friend from graduate school, Michael (RIP). It's not only cheap, it's fast! And you definitely have all the ingredients on hand. At the end of a long day, this can come together quickly, and the variations are endless. —JKF in NYC
long grain rice
cooked black beans (rinsed canned beans are fine)
cloves garlic, peeled and sliced thin
vinegar -- your choice, but I prefer sherry vinegar
Bring 2.5 cups of salted water to a boil. Add rice, bring back to the boil. Cover and cook on lowest flame for about 20 minutes.
Place the beans in a medium size saucepan, add salt and pepper to taste. (If you're using canned beans, you won't need salt.) Stir in garlic, oregano, hot sauce, cumin, vinegar and/or orange zest. (NB that this list of ingredients is a catch-all; you can make it with just oregano and vinegar, or try cumin with orange zest.) Bring to a simmer.
If you have it on hand, add diced chorizo or other sausage. If not, congratulate yourself for being a vegetarian -- today, at least.
When rice is done, fluff with a fork and spoon into bowls. Top with bean mixture and sprinkle chopped parsley over the top. If you like, sprinkle with a few drops of vinegar.