If you made the universe half of, say, beef, and half of gold, per weight, wouldn't it result in the same ol' universe coming to? Like wouldn't stars form and explode and create heavier elements and the whole shabang?

No, probably not. Stars rely primarily on fusing hydrogen, and heavier stars fuse helium. Only the most massive ones fuse heavier elements, to form elements near iron. If you started with a lot of carbon and oxygen (in beef)and gold, it's likely you would get clumps of mass that are as heavy as stars but would never "ignite". The gold would never fuse exothermically, and thus would be an impediment to the elements that could.

Ok so like, if I have a mass 2/3 the size of the universe (per mass) it wins over a mass 1/3 the size of the universe (per mass) correct?