Whats That Smell?

Today in science class we had to burn the two sugar cubes in our test tube. The Bunsen Burner was light as one of my classmates put on the glove and held the test tube with the sugar cubes in it over it. Suddenly, the bottom of the test tube started to have a brown substance fizzle up it and the sugar cubes slowly started to vanish. Then the brown substance rocketed up to the top and the bottom of the test tube was orange, and the top of the tube was a greenish yellowish color. After that, we all started to smell a burnt marshmellow or cotton candy kind of smell. We all went to go and look into the test tube and it was hardened. It was still brown but it had a hole in the middle and it looked like tar. Then my teacher, Mrs. Rousseau came over, wrapped the test tube in a towel, and broke it with a hammer so we could see it better. We took a little piece of it, observed it under a microscope, and it looked like a bunch of spider webs. Then after that we felt it and it was hard on one side and smooth on the other. Our prediction was that the hard side was what formed on the sides of the test tube, and the smooth part was on the inside. That lab was one of the funnest labs of the year, and it certaintly had me saying, what is that smell.