In a large bowl, cream together the butter and sugar.
Add the egg, cream, and lemon zest.
In a separate bowl, whisk together the flour, baking soda, and salt.
Add the flour in thirds to the creamed butter mixture just until the ingredients are blended, making sure not to over beat the dough.
Form the dough into two discs, wrap in plastic wrap and chill or freeze until ready to use.
Roll the dough to 1/8" inch, cut with desired cutters and bake in a 350-degree oven for 12-15 minutes or until lightly golden brown.