Finger food. That’s what we ask our guests to bring to our annual Labor Day Saturday party each year. No plates. No utensils. Just stacks of napkins. Basta. (Note to Beth: Cheesecake with fruit topping is no longer considered a finger food. Neither is soup.) To prime the savory table, I decided to try my first tortilla española, the famed potato and onion omelette we found in tapas joints and restaurants all over Spain. First, I sliced six medium Yukon gold potatoes in half, the halves into 1/8 inch slices. Fried them in olive oil and, with a slotted spoon, put them into a bowl. Then I minced and fried two onions and a shallot (from my friend James’s garden) and added them to the potatoes. Then came some chopped rosemary leaves, S&P and, once the bowl contents were cool enough, eight beaten eggs. Heated more oil in a sauté pan, poured in the mixture and let the bottom cook over medium heat. Then, once it was set, I finished cooking the top under the broiler until the whole thing felt firm. Loosen the edges. Flip onto a plate! And here it is, about to be cut into small squares, each skewered with a toothpick or set on a small piece of Jay’s homemade bread.