Everyone in my family loves spinach, but it doesn't meet my main gardening requirements as it is not fast-growing or heat-tolerant. Fortunately, there is a good spinach substitute that is. Propagated by root division, it does not meet my "roots easily from cuttings" requirement, but we can use division to get more plants. Komatsuna does well in the little pots that grow alongside our AeroGardens or out on the porch.
It is a cut-and-come again plant. The smaller leaves make a great salad green, and the larger ones are good in soup or stir fry.