Mix together the pesto and goat cheese with a spoon or fork, the fork will help break up the cheese. Add in tomatoes. Stir ingredients until the cheese is distributed and it's all incorporated. It needs to be very liquidy.
If the bowl you mix it in is the same bowl you serve it in, wipe the edges clean with a paper towel or cloth. This gives it a finished look, and you only use one bowl.
Now serve it as a side dish.
It's great with bread. The bread is really yummy dipped in the sauce this makes.