Cut each biscuit into fourths and roll each in a mixture of 1/3 cup granulated sugar and 2 teaspoons cinnamon. Drop all in greased Bundt pan.
Melt together: brown sugar, 2 teaspoons cinnamon, and butter. Add nuts. Pour over biscuits.
Bake at 350° for 30 minutes. Cool 20 minutes. Remove from pan.
Combine the bacon, cheese and onion; set aside. Cut each biscuit into fourths and dip in melted butter.
Layer a third of the biscuits in a lightly greased 10" Bundt pan. Sprinkle ½ of the bacon-cheese-onion mixture. Repeat, ending with top layer of biscuits.
Bake at 350° for 30-40 minutes (until golden). Cool 10 minutes in pan. Invert on a serving platter. Serve immediately.