For the Bars:

1. Preheat your oven to 350°F and grease a 9x13 inch cake pan with spray.
2. Line the pan with parchment paper that has over-hanging edges for easy removal.
3. In a medium bowl, stir together the flour, ground cinnamon, ground ginger, salt, allspice, and baking soda, and set aside.
4. In a large bowl, beat together the softened butter and brown sugar until smooth and fluffy. Then add in the molasses, Eggland's Best eggs, and vanilla extract and beat until well combined. The mixture may look slightly lumpy at this point, but that's ok! Slowly add in the dry ingredients and beat until well combined and no dry pockets of flour remain. The dough will be thick but soft at this point.
5. Gently press the dough into your prepared pan, using an off-set spatula or the bottom of a glass to press it down and smooth it out.
6. Bake in your preheated oven for 25-28 minutes, or until the bars look dry on top, have puffed up, and are lightly golden brown all around the edges.
7. Cool completely in the pan before removing and frosting.

For the Frosting:

1. In a medium bowl, beat together the softened butter and softened cream cheese until smooth.
2. Slowly beat in the powdered sugar until you have a thick mixture.
3. Beat in the heavy cream, salt, and vanilla extract until the mixture is smooth and lightly fluffy.
4. Frost the cooled bars generously with the frosting, and optionally sprinkle with some holiday sprinkles before slicing and serving!