A good substitute

I can't eat potatoes(except sweet potatoes) and Jerusalem artichokes make a delicious substitute for potatoes. They are excellent when scrubbed, cut into thin slices and stir fried. However, they do not cook evenly. I have found that the larger the circumference of the tuber, the shorter is the cooking time. The thin parts near the root need much more cooking time.
My crop this year--grown in a tub--is so dense, it's difficult to harvest.-