Combine butter, sugar, salt, and almond extract.
Add flour and combine until mixture becomes moist crumbs. Dough may come together-this is fine.
Set aside approximately 2 cups of this mixture (you can eyeball this).
Take remaining mixture and press into a well-greased 13 x 9 inch pan.
Warm preserves in microwave about 1 minute.
Spread preserves on top of crust layer.
Take the 2 cups of mixture you set aside and add almond paste until mixture is crumbly (if dough comes together while mixing just break it into crumbles).
Sprinkle the crumbles on top of the preserves and press down lightly.
Bake at 325 degrees until bars are lightly browned around edges and top is starting to brown (usually around 45 minutes).
Let cool.
Before bars get too set loosen the edges with a knife. These are easiest to cut and remove when nearly cooled completely.
Can be made ahead of time and stored in freezer.