Heat the milk in a saucepan until warm, then stir in the sugar and melted butter until dissolved. Sprinkle the yeast over the mixture and let it sit for 5 minutes until foamy.

In a large mixing bowl, whisk together the eggs, vanilla extract, ground cinnamon, and salt. Add the yeast mixture and mix well. Gradually add 4 cups of flour, stirring until a soft dough forms. Add more flour if the dough is too sticky.

Turn the dough onto a floured surface and knead for 5-7 minutes until smooth and elastic. Place in a greased bowl, cover with a towel, and let rise in a warm place for 1-2 hours until doubled in size.

Prepare the filling by mixing brown sugar, ground cinnamon, chopped pecans, raisins, and softened butter in a bowl until well combined.

After the dough has risen, punch it down and roll it out into a rectangle about 1/4 inch thick. Spread the filling evenly over the dough, leaving a small border. Roll the dough tightly into a log and shape it into a circle on a greased baking sheet.

Cover the shaped cake with a towel and let it rise for another 30-45 minutes until puffy.

Preheat the oven to 350°F (175°C). Bake the King Cake for 25-30 minutes until golden brown. Let it cool on a wire rack.

For the icing, whisk together powdered sugar, milk, and vanilla extract until smooth. Drizzle over the cooled cake and sprinkle with colored sugars.

Slice and serve the King Cake, enjoying the festive spirit of Mardi Gras!