Preheat oven to 350°F. Mix flour, 1 cup (2 sticks) of the butter, 1/2 cup of the sugar, almond extract and salt in large bowl with electric mixer on medium speed until mixture resembles coarse crumbs. Press mixture evenly into greased foil-lined 13x9-inch baking pan.
Bake 15 minutes or until golden brown. Sprinkle chocolate chips evenly over hot crust. Let stand 5 minutes. Spread melted chocolate over crust. Set aside.
Meanwhile, bring remaining 3/4 cup (1 1/2 sticks) butter, remaining 1 cup sugar and corn syrup to boil in heavy medium saucepan on medium heat. Boil 3 minutes without stirring. Remove from heat. Stir in rum flavor. Spread evenly over chocolate-covered crust. Sprinkle with almonds.
Refrigerate 1 hour or until set. Cut into bars. Store in tightly covered container at room temperature up to 5 days.