Whisk the flour baking soda, salt and spices together in a bowl and set aside.

In a saucepan, melt the butter over medium heat. If you want, you can melt and swirl until it starts to brown (this adds a little extra flavor).

Remove from heat and add the molasses and brown sugar. Stir until smooth, then scrape into a mixing bowl and let it cool slightly.

When the mixture is warm rather than piping hot, whisk in the egg and yolk.

Add the flour mixture and stir until you have a fully blended dough.

Divide dough into 4 sections. Press or roll each section into a very thin (less than ⅛ of an inch) slab. Do this on large pieces of parchment paper or plastic wrap. Carefully stack your slabs of thin dough on a baking sheet or tray and put them in the refrigerator and chill for several hours or until very firm.

Preheat oven to 300 degrees.

Remove one of the chilled thin slabs of dough from the refrigerator and use a cookie cutter to cut 2 inch shapes . Arrange shapes on a parchment or foil lined baking sheet. Repeat with a second slab of dough, fitting as many cookies as you can on the baking sheet but keeping them spaced by about an inch.

Bake for 15-18 minutes or until cookies appear set. Let them cool completely on a wire rack. They will crisp and become hard as they cool.