Ginger Snap Pumpkin Whoopie Pies

Ingredients

• 1 C vegetable oil
• 2 C packed brown sugar
• 1 tsp vanilla extract
• 2 large eggs, lightly beaten
• 3 1/2 C all-purpose flour
• 1 1/2 tsp aluminum-free baking powder
• 1 1/2 tsp baking soda
• 1 tsp salt
• 1 tsp ground ginger
• 1 tsp ground cinnamon
• 1/8 tsp ground cloves
• 1/8 tsp ground nutmeg
• 1/8 tsp ground allspice
• 1 3/4 C pumpkin puree (homemade or canned)
• 1 C softened butter
• 1/8 tsp salt
• 2 C confectioner's sugar
• 2 Tbsp milk
• 1/4 C flour
• 1/4 C Snap Liqueur or other Ginger Liqueur