1. In a bowl, sprinkle yeast over 6 tablespoons warm (about 110°) water; let stand until soft, about 5 minutes. Add sugar, 1 egg yolk, 6 tablespoons butter (cut into small pieces), and 1 1/2 cups flour; stir until evenly moistened.
2. To knead with a dough hook, beat at medium speed until dough pulls cleanly from bowl, about 5 minutes. To knead by hand, scrape dough onto a lightly floured board and knead until smooth, about 10 minutes, adding flour (as little as possible) if necessary to prevent sticking; return to bowl.
3. Cover dough with plastic wrap and let rise in a warm place until it's puffy enough to hold an impression when pressed with a finger (dough won't double in volume), about 1 hour.
4. With dough hook or your hands, punch air out of dough; lift dough from bowl and shape into a smooth ball. Set on the center of a floured pastry cloth or clean, smooth-textured dish towel. Pat dough flat; with a floured rolling pin, roll into a 14- to 15-inch square. Spread or evenly dot Almond Filling over dough to within 1 inch of edges. Lift cloth from one side to roll dough into a compact loaf. Gently lift loaf and lay seam down on a buttered 12- by 17-inch baking sheet. Pinch ends to seal, then fold under. Cover loosely with plastic wrap and let stand in a warm place until dough is slightly puffy, about 45 minutes.
5. In a small bowl, mix remaining egg yolk with milk. Brush loaf with yolk mixture; discard any remaining.
6. Bake loaf on the center rack in a 325° regular or convection oven until rich golden brown, about 45 minutes. Transfer to a rack and let cool at least 1 hour. Serve at room temperature. Cut crosswise into 1/4-inch-thick slices.
Almond Filling: In a food processor, whirl 1 cup unblanched almonds to fine meal. In a 10- to 12-inch nonstick frying pan, combine almonds, 3/4 cup raisins, 3/4 cup sugar, 3/4 cup milk, and 1 teaspoon grated lemon peel. Stir over high heat until mixture is thick enough to hold a clean trail for a few seconds when you draw a spoon across pan bottom. Stir in 1/2 teaspoon vanilla. Let cool at least 30 minutes.
Nutritional analysis per ounce.