Life on Earth is the result of a 4.6 billion year long cosmic recipe. The sun is the heating element and the Earth contains the ingredients.

I was thinking about how you can take 6 ingredients, mix them in a bowl, bake for an hour and have a cake. It made me think how the space between the upper atmosphere and the crust of the Earth is similar to an oven. The ingredients contain all the natural elements available. Set to bake for as many hours as there are sunlight available in any given day for 4.6 billion years, eventually the universe cooked up you and I.