Gingerbread Sheet Cake with Cinnamon Frosting (Gluten Free)

INGREDIENTS

1 2/3 sticks

unsalted butter, softened

1 cup

light muscovado sugar

medium eggs, room temperature

1/4 cup

molasses

1 1/2 cups

plain gluten free flour blend ((I use a simple store-bought blend of rice, potato and maize flour with no added xanthan gum))

1/4 tsp

xanthan gum

1 1/2 tsp

baking powder

1/2 tsp

baking soda

salt

2 tsp

ground cinnamon

1 1/2 tsp

ground ginger

1 tsp

ground allspice

1/4 tsp

ground cloves

1/2 cup

milk, room temperature

2 1/2 sticks

unsalted butter, softened

1 1/2 cups

powdered/icing sugar, sifted

2 tsp

ground cinnamon

1/2 cup

heavy/double cream

sprinkles (for decoration)