In a large microwave-safe bowl, combine the sugar and cornstarch. Then stir in the raspberries.
Microwave on high for 2 minutes; stir. Continue to microwave in 1 minute intervals for several minutes, or until the mixture has thickened. (It will be slightly more runny than a jam.) Set aside.
Cream the butter and sugar. Add almond extract and eggs. Stir in the flour and salt and mix well.
Spread ⅔ of the batter into a greased 9x13" pan.
Spread the raspberry filling on top. Drop the remaining batter by teaspoons on top of the filling.
Bake in a preheated 350 degree oven for 30-40 minutes, or until golden brown on top.
Stir together the powdered sugar and drizzle over the slightly cooled bars.