Heat the olive oil in a small skillet. Add the tomatoes and garlic and saute, stirring occasionally, for about 10 minutes or until the tomatoes form a puree that will mound. Let cool.
Put the butter in a mixing bowl and beat in the tomatoes and remaining ingredients. Can be made up to 2 days ahead and refrigerated but best served at room temperature so that it will melt quickly over the fish, chicken or pasta.