Whisk warm milk, yeast, and 1 teaspoon sugar in a small bowl. Let sit 5–10 minutes until foamy.

In a large bowl, combine melted butter, remaining sugar, eggs, vanilla, and orange zest. Stir in the foamy yeast mixture.

Add 3 1/2 cups flour and salt, stirring until a sticky dough forms. Turn onto a floured surface and knead, adding the rest of the flour as needed, until smooth and elastic (5–7 minutes).

Place dough in a lightly oiled bowl, cover with a clean towel, and let rise in a warm spot until doubled, about 60–90 minutes.

While the dough rises, beat together cream cheese, sugar, egg yolk, vanilla, and flour until silky.

Punch down dough and divide in half. Roll each half into a long rope about 18–20 inches. Flatten each rope into a strip 1/2 inch thick, spoon a line of cream cheese filling along the center, leaving 1/2 inch at both ends.

Fold dough over the filling and seal edges, rolling gently to form even ropes. Braid the two ropes together and form into a ring, pinching ends to seal.

Place the ring on a parchment-lined baking sheet, cover, and let rise 30–45 minutes until puffy.

Preheat oven to 350°F (175°C). Brush the ring lightly with beaten egg for a glossy finish.

Bake 20–25 minutes until golden brown and the center registers about 190°F.

Cool for 10–15 minutes. Whisk powdered sugar, milk, and vanilla to a pourable glaze.

Drizzle over the ring and sprinkle with purple, green, and gold sanding sugars in sections.

Let glaze set 10 minutes before slicing. Serve warm.