cup butter, softened
cups buttermilk or 2 cups milk plus 2 T vinegar or lemon juice
tsp baking soda
Cream together butter, 2 cups sugar, and eggs. Add milk, flour, and baking soda. Put 1/2 of batter (or a little less) into greased loaf pans. Mix in separate bowl the 2/3 cup sugar and cinnamon. Sprinkle 3/4 of cinnamon mixture on top of the 1/2 batter in each pan. Add remaining batter to pans; sprinkle with last of cinnamon topping. Swirl with knife. Bake at 350 for 45-50 min or until toothpick tester comes clean. Cool in pan for 20 minutes before removing.