Leftovers are a busy person's best friend. Sure, you can just create a plate of what you ate last night, stick it in the microwave, and zap it into heated molecules that don't quite taste as good as they did the first time around. But with a little ingenuity, you can turn them into something new.
Fall in love with leftovers. You'll wonder why you didn't do it before.
Kitchen sink casserole (serves however many . . .)
Layer 1: something liquid. Soup. Tomatoes. Spaghetti sauce. Stock. Water. Wine. You don't need a lot of this, but a layer of liquid-y stuff on the bottom of the casserole pan will keep it from sticking.
Layer 2: something starch. Cooked rice. Pasta. Quinoa. Potatoes. Cubed and dried bread. You could also do denser vegetables like sweet potatoes or winter squash, or cauliflower.
Layer 3: something veggie or protein or both. In this video, I had a pile of leftover pizza toppings (yes, even some pineapple bits!) that were a perfect combination of all of the above. You can also open a can of beans, drain them, and scatter them on top of the starch layer. Could also grab a bag of frozen veggies to the same effect.
Layer 4: Cheese, baby, cheese. Because it melts and gooeys all of the rest of the stuff together. Got a combination of cheeses? Toss them on here. Got leftover white sauce or cheese sauce? Drizzle it on.
Bake this concoction in a 350 degree oven for about 30 minutes or until the cheese is melted and starting to turn brown. The bonus is that everything is already cooked, so all you're doing is reheating. YUM.