In a bowl, cream together the sour cream, butter and sugar until the mixture starts to rise and lighten in color.
Add in the eggs, one by one, beating after each addition. Then mix in the vanilla.
In a different bowl sift the flour, salt, baking powder and baking soda together.
Add a third of the flour mixture to the butter one, then stir in half of the buttermilk, then the next third of the flour, then buttermilk and the rest of the flour, so, alternating, starting and finishing with the flour mixture.
In a bowl, combine the flour, sugar, cinnamon, salt and pecan nuts together.
Add in the melted butter and mix until a paste like mixture forms.
Preheat the oven to 350°F (180°C)
Pour half of the mixture into a rectangular pan, previously greased and floured, then spread over it half of the nuts mixture and run a wooden stick through it to combine just a little both mixtures.
Do step 2 again.
Bake at 350°C (180°F) aporx. until a wooden stick comes out clean when you insert it.
Once ready and completely cooled down, turn out and cut into squares.
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