In a small bowl, dissolve yeast in warm water and set aside. In a large bowl mix milk, sugar, melted butter, salt and egg. Add 2 cups of flour. Mix until smooth. Add yeast mixture. Mix in remaining flour until dough is easy to handle. In a stand mixture, knead dough about 5-7 minutes. Place dough in a large greased bowl, cover and let rise until dough has doubled in size. This will usually take any where from 1 to 1 1/2 hours.
Once the dough has doubled in size, punch down the dough. Roll dough out on a floured cutting board into a 15 by 9 inch rectangle. Spread melted butter all over the dough. In a small bowl mix sugar and cinnamon and then sprinkle over buttered dough. Then sprinkle with walnut, pecans, and/or raisins if desired. Beginning at the 15 inch side, roll up dough and pinch the edges together to seal. Cut dough into 12 to 15 slices.
Coat the bottom of a 9x13 (or bigger) pan with butter and sprinkle with sugar. Place cinnamon rolls slices close together in the pan. Lightly cover and let rise until dough has doubled in size, about 45 minutes. Bake for 25-30 minutes, until nicely browned.
Meanwhile, mix butter, powdered sugar and vanilla. Add hot water 1 tablespoon at a time until the glaze reaches desired consistency. Spread over cooled rolls.
**Save extra in a sealed container for later use. Cinnamon rolls will keep in a sealed container for about 5 days. If they get a little hard you can warm them in a microwave to soften. **I doubled the glaze recipe to have extra on hand.