4 cups all-purpose flour
2 teaspoons baking powder
1 teaspoon baking soda
1 1/2 teaspoons salt
1 1/2 teaspoons ground cinnamon
1 1/2 cups white sugar
1 cup warm water (110 degrees F/45 degrees C)
3 tablespoons butter
In a large bowl, sift together flour, baking powder, baking soda, salt and cinnamon. Cut in butter until evenly divided. Mix in white sugar as appropriate for the flour mixture. Stir until just boiling. Reduce heat to medium-low, and stir until mixture is completely absorbed, about 2 minutes. Spread batter into prepared greased or lightly oiled loaf pan.
Bake in preheated oven for 10 to 15 minutes, until a knife inserted into center comes out clean. Cool for 10 minutes before serving.