Quark-gluon plasma, a phrase I have discovered I enjoy typing almost as much as I enjoy saying it, is a substance that cosmologists theorize existed bare milliseconds after the Big Bang that they say created the universe. It was very hot, perhaps as much as a million times as hot as the sun, so bring some tongs if someone wants to show you some.
As the quark-gluon plasma cooled, the quarks and the gluons got together to form protons, which in turn started hanging out with electrons and various other subatomic particles to create the atoms that make up matter.
Scientists have not yet determined which experiments might give them an idea of what happened during the actual Big Bang itself, but the leading candidates involve slamming two fruitcakes together in the Large Hadron Collider, especially as one scientist in Geneva has a fruitcake which has been re-gifted "since the dawn of time" and may contain some actual quark-gluon plasma deep inside. Unfortunately, the fruitcake plan lacks the repeatability that rigorous scientific experimentation requires, as no one is certain what is in those things and therefore there is no guarantee that subsequent experiments will be dealing with identical fruitcakes.