Preheat oven to 350 degrees F. Set aside 2 tablespoons of the butter. Place remainder of the butter in a large mixing bowl. Beat with an electric mixer at medium speed for 30 seconds. Add brown sugar; beat until well blended. Add eggs, 1 teaspoon vanilla, and 1 teaspoon almond extract. Beat until well blended.
In another large bowl, combine flour and baking soda; add oats; mix well. Gradually add flour-oat mixture into butter-egg mixture; mix well; set aside.
In a medium saucepan, combine the reserved 2 teaspoons butter, sweetened condensed milk, and chocolate pieces. Cook over low heat about 7 minutes, stirring occasionally, until chocolate melts. Remove from heat. Add chopped almonds, cardamom, and remaining 1 teaspoon each of the vanilla and almond extracts. Mix well.
Using your hands, press ⅔ (about 3-½ cups) of the oat mixture into the bottom of an ungreased 15x10x1-inch baking pan. Using the back of the rounded part of a large spoon, spread chocolate mixture over the oat mixture. Using your finger, dot the remaining oat mixture over the chocolate.
Bake about 25 minutes, or until the top is lightly browned (chocolate mixture will still look moist). Cool in the pan on a wire rack. While still warm, cut into 2x1-inch bars. Gently press a toasted almond half into top of each bar. Cool completely.