Preheat oven to 350°F (175°C). Grease and line a 9-inch round pan or loaf pan with parchment paper. Place your cut sweet potatoes in the bowl of a food processor and process until finely grated. In a small bowl, toss raisins in 2 teaspoons flour from the ½ cup. Set aside. In a large bowl, combine grated sweet potatoes, light brown sugar, all-purpose flour, vanilla extract, allspice, cinnamon, nutmeg, ginger, and salt. Stir in 1½ cups of coconut milk until a batter forms. Fold in the raisins that were tossed in the flour. Pour the batter into the prepared pan and smooth the top. Bake uncovered for 1 hour 30 minutes, until mostly set but still slightly soft in the center