FOR THE COOKIES: – 2 cups (240g) all-purpose flour – 1 teaspoon baking powder – 1/2 teaspoon baking soda – 1/2 teaspoon salt – 1 teaspoon ground cinnamon – 1/2 teaspoon ground ginger – 1/2 teaspoon ground nutmeg – 1/4 teaspoon ground allspice – 1/4 teaspoon ground cardamom – 2 cups (160g) quick cooking oat – 3/4 cup (170g) unsalted butter, softened – 1 & 1/4 cups (250g) firmly packed light brown sugar – 2 large egg – 1 teaspoon vanilla extract FOR THE ICING: – 2 cups (220g) confectioners’ sugar, sifted – 2 to 4 tablespoons milk