To make the sugared cranberries, in a medium saucepan over medium heat, combine 1/4 cup sugar and water. Stir until sugar is dissolved, about 3 minutes. Stir in cranberries until well coated. Using a slotted spoon, transfer cranberries to a wire rack to dry for one hour. After one hour, roll cranberries in remaining 1/2 cup sugar until well coated. Let dry for an additional hour.
To make the cupcakes, preheat oven to 350 degrees F. Line a 12-count muffin pan with cupcake liners; set aside.
In a medium bowl, add the flour, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, and allspice. Stir to combine; set aside.
In the bowl of a stand mixer fitted with the paddle attachment, beat together the butter and brown sugar on medium speed until creamy. Add the egg and mix until combined, scraping down the sides of the bowl as needed. Beat in the milk, molasses and vanilla until combined. With the mixer on low speed, gradually add the dry ingredients to the wet ingredients. Scrape down the sides of the bowl as needed.
Divide the batter evenly between the prepared liners, filling each about 2/3-full. Bake until a toothpick inserted in the center comes out clean, about 18 to 20 minutes, rotating the pans halfway through baking. Let cool in the pan about 5 to 10 minutes, then transfer to a wire rack to cool completely.
To make the frosting, combine the cranberries, water and sugar in a medium saucepan over medium heat. Bring the mixture to a boil. Lower the heat and let simmer uncovered, about 15 minutes, until the cranberries have popped and the sauce is thickened. Remove from heat and let cool completely. Sauce will thicken as it cools. Reserve ¼-1/3 cup and store the rest in an air-tight container in the fridge for up to 1 week.
In the clean bowl of a stand mixer fitted with the paddle attachment, Add butter to the clean bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed for 30 seconds. Add the confectioners’ sugar and mix until light and fluffy, about 4 minutes. Add cranberry mixture, a tablespoon at a time, until desired color and flavor is reached. Beat on high for about 30 seconds to lighten the frosting.
Pipe frosting onto each cupcake. Top with sugared cranberries. Enjoy!