In large bowl cream butter, sugar and vanilla until light and fluffy.

Add eggs one at a time mixing well.

Mix in bananas and sour cream.

Mix flour, baking soda and salt well then add to wet mixture. Using a spoon, gently fold mixture to incorperate flour. Do not over mix.

Preheat oven to 350 degrees and grease and flour a 12 cup bundt pan.

Gently and evenly pour batter into bundt pan. Spread evenly and tap out air bubbles.

Bake for 50 to 60 minutes. If browning to much cover with foil and check at 50 minutes. If not quite done, cook until knife inserted comes out clean.

Cool in pan for 10 minutes then turn out onto cooling rack to cool completely.

When cake has cooled, in saucepan mix butter, brown sugar and milk. Simmer until sugar is melted. Stir frequently.

Remove from heat and add vanilla and powdered sugar. Stir briskly and pour glaze over cooled cake. This glaze sets fast so work quickly. Garnish with chopped nuts. You can also use nuts in the cake instead.