Preheat oven to 350°F. Grease 15"x10"x1" baking pan.
With an electric mixer, cream butter, sugar and salt for 5-7 minutes.
Add eggs 1 at a time, beating well (at least 1 minute) after each addition.
Mix in vanilla and almond flavoring. Gradually add flour.
Spread 3 cups batter into greased pan. Top evenly with pie filling.
Place remaining batter into piping bag (or gallon baggie). Cut off tip and pipe remaining batter evenly across top in lines going side-to-side and then top-to-bottom. Be careful not to press top batter into filling.
Bake at 350°F for 35-45 minutes until golden brown. Cool completely on wire rack before icing, about 3 hours.
To make glaze: In a small bowl, mix 1 cup powdered sugar, ½ teaspoon vanilla, and ½ teaspoon almond extract. Add milk 1 Tablespoon at a time until desire consistency is reached.
Pour glaze into piping bag or baggie. Cut off tip and drizzle over top of completely cooled bars.
Allow glaze to harden before slicing, about 30-60 minutes.
Serve warm, cold or room temperature.
Store at room temperature up to 1-2 days or in the fridge for up to 4-5 days.