A supersaturated solution can be prepared by dissolving solute in solvent while adding . A supersaturated solution contains more than can ordinarily be dissolved in the solvent at room temperature. A solution may remain supersaturated until is initiated, often by adding solid to the solution or by allowing solvent to evaporate.

Heat, solutes and high temperature.

Explanation:

A supersaturated solution can be formed by dissolving solute more solute in solvent by increasing temperature of the solution. A supersaturated solution contains more quantity of solutes than can be dissolved in the solvent at room temperature. A solution may remain supersaturated until the solution has high temperature and when the temperature started lower, the extra dissolve solutes begin undissolved and remain suspended in the solution.

if you're asking what comes out, it's steam.