Cook first 4 ingredients in a saucepan over low heat, stirring often, until butter melts; cool mixture to 100 degrees to 110 degrees.
Dissolve yeast and 1/2 tablespoon sugar in 1/4 cup warm water in a large bowl; let stand 5 minutes; add butter mixture, egg, and 1 cup flour; beat at medium speed with an electric mixer 2 minutes or until smooth; gradually stir in enough remaining flour to make a soft dough.
Turn dough onto a lightly floured surface; knead until smooth and elastic, about 10 minutes; place in a well-greased bowl, turning to grease top; cover and let rise in a warm place (85 degrees), free from drafts, 1 hour or until doubled in bulk.
Using an electric mixer, mix cream cheese until smooth; add egg and blend well; add sugar, salt and vanilla and mix until smooth and creamy; set aside.
Punch dough down; turn out onto a lightly floured surface; roll to a 28- x 10-inch rectangle; lightly sprinkle with cinnamon and sugar.
Spread cream cheese mixture on dough; roll dough, jellyroll fashion, starting at long side; place dough roll, seam side down, on a lightly greased baking sheet; bring ends together to form an oval ring, moistening and punching edges together to seal.
Cover and let rise in a warm place, free from drafts, 20 minutes or until doubled in bulk.
Bake at 375 degrees for 15 minutes or until golden.
Drizzle frostings and sprinkle with colored sugars.
Frosting
Stir together powdered sugar and melted butter.
Add milk to reach desired consistency for drizzling; stir in vanilla.
Colored Sugars
Place 1/4 cup sugar and drop of green food coloring in a zip-top plastic bag; seal, shake, and squeeze vigorously to evenly mix color with sugar.
Repeat procedure with 1/4 cup sugar and yellow food coloring; For purple, combine 1 drop red and 1 drop blue food coloring before adding to remaining 1/4 cup sugar.
Notes
Cut recipe in half (original made 2 cakes)
Changes made based on a number of reviews
Reduced the amount of frosting by 33%
Right before adding the filling, lightly sprinkle cinnamon and sugar on the rolled out dough
Add 1 tablespoon cornstarch to each cup of flour in order to make “cake” flour
McCormick food coloring is muddy when you mix red and blue, so you might consider buying Wilton for the purple.