Separate them. Always.

Separate, without question.

Pasta is a sponge. Leave it sitting in sauce overnight and it soaks up all the liquid, turning into bloated, mushy noodles. The sauce meanwhile thickens into a paste. Neither is good.

Store the pasta in one container, tossed with just a tiny drizzle of olive oil (or butter) to keep it from clumping. Store the sauce in another container. When you reheat, warm the sauce first, then toss in the pasta and cook together for 30 seconds to marry them again.

If you’re lazy and thinking about just throwing it all in one Tupperware, fine—but then you’re eating pasta salad tomorrow, not spaghetti. For best texture, separate.

Your future self will thank you at lunch.