Coca de Acelgas

Prepare dough: Combine yeast with 2 tbsp of water and let sit at room temperature for a few minutes. In a large bowl, sift flour, add salt, yeast, and water. Knead by hand until smooth and elastic. Roll up to a ball, place in lightly oiled bowl, and cover with plastic. Proof in a warm place for about 1 hour. Topping: Discard dark green parts of leek, cut lengthwise, then slice thinly. Wash thoroughly under cold water and blot dry with paper towels. Remove stems from the chard, discard all hard pieces. Roughly chop the leaves and mince the stems. Heat olive oil over medium heat, add leeks and garlic, and cook until the leek has softened, stirring occasionally, about 10 minutes. Add the chard stems, cook until stems are tender, about 5 minutes. Turn heat to high and add the leaves. Cook until leaves are wilting, about 5 minutes. Turn heat to low, add lemon zest, raisins, pine nuts, and sun-dried tomatoes. Warm through and season to taste with salt and pepper. Set aside to cool. Preheat oven to 450 degrees. Punch dough down on a floured work surface. Pat into a long flat oval shape about a quarter inch thick. Place dough on an oiled baking sheet. Top with Swiss chard mixture and bake for 20 minutes or until golden brown. Cut into small, appetizer sized pieces.