Generously spray 15 x 10 x 1″ jellyroll pan with nonstick cooking spray. Sprinkle bottom and sides with breadcrumbs. Prepare crust: Into large bowl, sift together flour, Sweet ‘N Low, sugar, and baking powder. With pastry blender, cut in 3/4 cup margarine until mixture resembles fine cornmeal. With fork, beat in 1 egg and egg yolk; knead with hands to make a smooth dough. Shape into a ball; divide in half. Between 2 sheets of waxed paper, roll out half of dough to fit in half of pan, from center to one end. Tuck in overhang even with top of pan. Repeat with other half of dough, fitting into other end of pan. Press edges of dough together in center. Refrigerate. Preheat oven to 325F. Prepare filling: In medium-sized bowl with mixer at medium speed, beat almonds, confectioner’s sugar, margarine, Sweet ‘N Low, Butter Buds, and almond extract until well mixed. Beat in egg whites and 2 eggs, one at a time, beating well after each addition. Spread jam over chilled crust. Top with almond filling. Bake 15-20 minutes or until top is golden and crust pulls away from sides of pan. Cool in wire rack. Spread remaining jam over top. To serve, cut horizontally into 8 parts and vertically into 7 parts.