What can I substitute for preserved lemons?
I'd recommend fresh lemon zest and juice (or meyer lemon) and a little extra salt.
I'd recommend lightly sauteeing for a minute or two a couple of seeded lemon slices in just a touch of light oil with some salt, then putting it in the oven (in the skillet) for ten to twelve minutes in a moderate oven, adding a pinch of salt and a tablespoon or two of water, to prevent the juices from getting too sticky. Then I'd chop it and use it with the pan juices. Preserved lemon has a somewhat more mellow, less acidic quality than fresh lemon, which is why I would not substitute fresh.
I was cooking chicken tajine and couldn't find preserved lemons here in Macon, Georgia (it is the deep south after all) and I used the raw lemon juice for the marinade and then on cooking day I sliced the lemons thinkly and stewed them at the same time as the chicken and the dish was perfect! I am not sure I want to go to the extreme of picking my own lemons or the expense of buying them already done. I think the cooking most definitely sweetened the lemons adding mellow lemon flavoring to my dish.