Place bread cubes in a greased 13x9-in. baking dish. In a bowl, whisk eggs, milk, ¾ cup brown sugar, cinnamon and nutmeg; pour over bread. Cover and refrigerate for 8 hours or overnight.
Remove from the refrigerator 30 minutes before baking. Preheat oven to 400°. Sprinkle almonds over egg mixture. Combine melted butter and remaining ¼ cup brown sugar; drizzle over the top.
Bake, uncovered, for 25 minutes. Sprinkle with raspberries. Bake until a knife inserted in the center comes out clean, about 10 minutes longer. If desired, sprinkle with confectioners' sugar and serve with syrup.
