Place frozen loaves on a tray and thaw at room temperature. This may take 3 to 4 hours. You can also thaw in the refrigerator overnight.

Spray 8-inch bread pans with non-stick cooking spray. Set aside.

Cut 4 deep cuts into each loaf of bread, nearly all the way through, leaving just a small piece still connected at the bottom.

Coat bread completely with the melted butter, making sure to coat the inside of each cut very well.

Mix the sugar and cinnamon together in a wide dish and roll the bread gently in the cinnamon sugar. Make a thick coat and stuff each cut with lots of cinnamon sugar.

Place a loaf of bread in each pan and cover with a light tea towel. Allow bread to rise in a warm area, until doubled in size, about 1 hour.

Preheat the oven to 350°F.

Bake bread for 20 to 25 minutes. Loaves will be golden brown and when thumped on the bottom should sound hollow. Remove bread from oven and allow bread to cool for about 10 minutes.

While the bread is cooling, mix up the icing. Combine the powdered sugar, vanilla and 2 tablespoons of milk and whisk until smooth. Add extra milk as needed, until desired consistency. Drizzle icing on top of warm bread and serve!