Combine raspberries and brown sugar in a bowl. Set aside.
Combine flour and next 4 ingredients (flour through salt) in a large bowl. Combine yogurt, margarine, 1 teaspoon vanilla, and egg in a small bowl; stir well. Add to flour mixture, stirring just until moist. Spoon two-thirds of batter into an 8-inch round cake pan coated with cooking spray; spread evenly. Top with raspberry mixture. Spoon remaining batter over raspberry mixture; top with almonds.
Bake at 350° for 40 minutes or until a wooden pick inserted in center comes out clean. Let cool 10 minutes on a wire rack. Combine powdered sugar, milk, and 1/4 teaspoon vanilla; stir well. Drizzle over cake. Serve warm or at room temperature.