In a small cup or bowl, stir the yeast into water to soften. In a large bowl, cream the butter, almond paste and sugar until light and fluffy. Add the softened yeast, lemon peel, vanilla, salt, eggs, egg yolk, milk, and 3 cups flour to the creamed mixture. Beat vigorously for 2 minutes. Gradually add flour, 1/4 cup at a time, until the dough begins to pull away from the side of the bowl. Turn the dough out onto a floured work surface. Knead, adding flour a little at a time, until you have a smooth, elastic dough. Put the dough into an oiled bowl. Turn to coat the entire ball of dough with oil. Cover with a tightly woven towel and let rise about 1 1/2 hours. Due to the almond paste, this recipe doesn't double in size. Turn the dough out onto a lightly oiled work surface and divide in half. Shape each half into a smooth ball. Cover and let rest 5 minutes. Shape one ball of dough into a half oval 12 inches wide and four inches high at the center. Place in the center of a parchment-lined baking sheet. Flatten the center slightly so that when the next piece of dough is laid across it, it won't be so thick. Shape the other ball of dough into an 8 by 16 by 16-inch triangle Keep the points of the triangle rounded rather than pointed. Lay the triangle, centered, on the flattened part of the half oval. Fold the narrow end over to make the head. Pinch with your fingers to form a beak into the top side of the dough. Fold the other end in the opposite direction to form the tail. Cut 2-inch slits along the bottom edge of the tail and wing tips. Fan them out as for feathers. Cover with a towel and let rise 45 minutes. Again, due to the almond paste, the dough won't rise as high as other types of yeast dough; however, it does rise high during baking. 1. About 10 minutes before baking, preheat the oven to 375 degrees. 2. Just before baking, beat the egg white until frothy. Lightly brush the dove with the beaten egg white and place thinly sliced almonds, overlapping slightly, on the tail and wings to simulate feathers. Use a small bit of an almond to make the dove's eye (diagram 7). Carefully brush the almond "feathers" with the remaining beaten egg white then sprinkle the dove with granulated sugar. 3. Bake for 20 minutes. Cover the bread loosely with foil with the shiny side up. Continue to bake for 10 more minutes, or until the internal temperature of the loaf reaches 190 degrees. 4. Immediately remove dove from baking sheet and cool on a rack.