1. Dissolve the baking soda in the hot water.
2. Stir in 1 tablespoon of sugar and molasses, then mix in the cranberries and flour.
3. Pour into a greased 6 cup steamer mould.
4. Cover the mould, and place into a steamer basket over boiling water.
5. Cover the steaming pot.
6. Cook over medium heat for one hour before checking, but it will take about 1 1/2 hours total.
7. A toothpick inserted into the pudding should come out clean.
8. Loosen the edges, and cool on a wire rack in the mould.

Make the Hard Sauce just before Serving:

1. Heat the unsalted butter, cream, 1 cup sugar and vanilla in a small saucepan over medium heat.
2. Cook stirring constantly until heated through and smooth.