Preheat oven to 350ºF. Butter and flour a 10 x 6 baking dish. (I used an 8 x 8)
In a small bowl, combine chopped pecans, brown sugar and cinnamon and toss to mix.
In a large bowl, combine melted butter, white sugar, eggs, sour cream and vanilla. Mix well.
Stir in the flour, wheat bran, salt and baking powder and mix until just combined. Do not over mix.
Spoon/spread half the batter into the prepared baking dish. Sprinkle on half of the nut mixture. Cover with the remaining batter and sprinkle the rest of the nut mixture on top.
Bake until golden on top and firm, about 40 - 50 minutes. Cool on a rack for at least 10 minutes. Serve warm.