Preheat oven to 350°.
To prepare cake, coat 2 (9-inch) round cake pans with cooking spray; line bottoms of pans with wax paper. Coat wax paper with cooking spray; set aside.
Place 2 cups sugar and unsalted butter in a large bowl; beat with a mixer at medium speed for 5 minutes or until well blended. Add eggs, 1 at a time, beating well after each addition. Beat in 1 teaspoon clear vanilla extract and 1/2 teaspoon almond extract.
Lightly spoon flour into dry measuring cups; level with a knife. Combine flour, baking powder, baking soda, and 1/2 teaspoon salt, stirring with a whisk. Add flour mixture and buttermilk alternately to sugar mixture, beginning and ending with flour mixture, and mix after each addition. Pour batter into prepared cake pans. Sharply tap pans once on counter to remove air bubbles. Bake at 350° for 30 minutes or until a wooden pick inserted in center comes out clean. Cool cake in pans for 10 minutes on a wire rack; remove cake from pans. Carefully peel off wax paper, and cool completely on wire rack.
To prepare icing, place cream of tartar and egg whites in a large bowl; beat with a mixer at high speed until soft peaks form.
Combine 1 cup sugar, 1/4 cup water, and 1/4 teaspoon salt in a small saucepan. Cook over medium heat until sugar dissolves, stirring mixture frequently, and bring to a boil. Cook, without stirring, for 2 minutes or until a candy thermometer registers 238°. Pour hot sugar syrup in a thin stream over egg whites, beating at high speed until stiff peaks form. Stir in 1 teaspoon vanilla extract and 1/2 teaspoon almond extract. Place 1 cake layer on a plate; spread cake layer with 2 cups icing. Top with the remaining cake layer. Spread remaining icing over top and sides of cake.