Capers are weird little things. They have a kind of pungent, cabbagey taste. I like them. In the shops, capers come in two versions: salted and pickled. I like to buy things locally if I can, but there are some things you have to buy imported...Herbs and spices, olives, balsamic vinegar - stuff like that. And capers. I bought my first jar of capers in Armenia - salted ones, imported from Italy - and they cost a fortune. I thought they were worth it, though. They would last for ages and I could try them out in lots of new recipes. A few days later I found out that capers grow in Armenia and I bought a big jar of local, pickled capers. Three times the quantity at a third of the price. They were organic, too. That's the way it goes. Life I mean. Things like that happen and I suppose I could have looked on the negative side and said, 'I just wasted all that money buying a wee jar of Italian capers when I didn't need to.' but I didn't. I thought to myself, 'Now I have both salted and pickled capers and I can experiment with them to see what the difference is'. But you know what? There isn't much difference at all. I mean there is a difference - salt, vinegar - big difference, but the taste of the capers is so strong and distinctive that the difference doesn't amount to much. The only thing to remember is that you should rinse the salted ones before using them.
Incidentally - and this is probably one of the most useless things I could tell you - you can substitute pickled green nasturtium seeds for capers. All you need to do is, before you start the recipe, go and buy a packet of nasturtium seeds, plant them, wait till they flower and the flowers die and produce soft green seeds, collect a big handful, blanch them and steep in vinegar for a week or two. Right, now you've done that we can get on with the recipe. The rest is very simple (especially compared to pickling the nasturtium seeds).
Wash and roughly chop the spinach and lettuce. Add the olives, capers and spring onions. Put the oil, vinegar and oregano in a glass or small jar. Just before serving, cover the jar tightly (you can use your hand), shake vigorously and pour the dressing over the salad. Toss and serve.