Some salt, vegetables and spices are added to some hot water. The salt disappears into the water, the vegetables sink to the bottom and the spices...

A solution is a homogeneous mixture of substances, meaning that the substances are evenly distributed. It consists of two types of components, a solvent and one or more solutes. The solute is dissolved in the solvent. The solvent is usually present in a greater amount.

In this mixture salt is a solute. It doesn't actually disappear; it becomes invisible on a macroscopic level when it dissolves. Since it's observed to dissolve we can assume that it becomes evenly distributed. 

Water is behaving as a solvent, dissolving the salt. The phase of a solution, which is liquid in this case, is that of the solvent.

The spices and vegetables don't dissolve and aren't part of the salt water solution. This is actually a mixture within a mixture. The overall mixture is heterogeneous with one of its components, salt water, being a solution.