Heat oven to 350 degrees F. Grease a 12-cup capacity bundt pan with 1 tablespoon of the butter. Add a little flour, tilting pan so flour sticks to butter (step A, below).Advertisement
Measure 2 3/4 cups flour (step B); pour into small bowl; add baking soda and salt. Whisk together to blend.
In large bowl, beat remaining butter and the sugar on high speed just until pale and fluffy (step C). Beat in eggs, one at a time, until smooth. Add vanilla.
On low speed, beat in half of the flour mixture, then sour cream mixture. Beat in remaining flour mixture just until blended.
Spoon batter into prepared pan. Bake at 350 degrees F for 1 hour, until cake springs back when pressed. Cool in pan on rack for 10 minutes. Place rack over cake, carefully flip to release cake from pan; cool.
Blend confectioners' sugar and 1 to 2 tablespoons water until smooth. Place cake on rack over parchment paper. Pour glaze over, letting it drip down side.
After greasing the baking pan, sprinkle with about 2 tablespoons flour. Working over the sink or a garbage can, tilt and turn pan, tapping gently, and coat butter with flour. Discard excess.
Spoon flour into a measuring cup and then level by sweeping a knife or spoon handle across top. This ensures that your flour doesn't get packed in, which can make the cake too dense.
Beat butter and sugar on high speed just until they turn pale and fluffy but are still grainy, about 3 to 5 minutes.