In a small bowl, combine chopped dried apricots and 1/4 c run. Let stand 20 minutes.
Heat oven to 325º. Generously grease and flour a 10-inch Turk's turban mold or tube pan.
In a food processor or blender process apricot halves until pureed. Stir in dried apricots with rum.
In a large bowl, with electric mixer beat butter, sour cream, eggs, vanilla, and sugar until well blended.
Add flour, salt, baking soda, and apricot puree mixture. Beat at low speed just until combined, scraping side of bowl frequently.
Pour batter into prepared pan. Bake 1 1/4 hours or until toothpick inserted in center comes out clean. Cool in pan 5 minutes. Loosen edges, invert and unmold cake onto flameproof plate with rim.
In small saucepan, heat apricot preserves. Strain and stir in 1/4 cup rum. Brush apricot glaze over cake every few minutes while it's cooling until all glaze is used.
If desired, garnish cake plate with clusters of seedless green grapes and fresh leaves. Bring cake to serving cart or side table. In a long handled ladle, gently warm remaining rum until vapors rise. Ignite and pour over cake. When flames subside, slice cake and serve.