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.
I really enjoyed this simple, but tasty recipe. I used the basic recipe, but changed a few things based on what I had on hand. Instead of fresh raspberries, I added frozen, and I mixed the berries into the batter then poured it into the pan instead of dividing the batter. Because I was craving strong almond flavor but didn't have almonds, I added a diced up chunk of almond paste (maybe 1oz.) to the batter when I added the raspberries. I also substituted 1tsp. almond extract for the vanilla extract. (The vanilla flavor came through the vanilla yogurt I had on hand.) I would definitely make this recipe again, whether it's as is or with the substitutes. I did find that I only had to bake it for 30 minutes instead of 40.