Preheat the oven to 350 degrees F. Line a heavy large baking sheet with a silicon pad or parchment paper. Combine the water, butter, and salt in a heavy medium saucepan over medium heat. Bring to a boil, stirring until the butter melts. Add the flour and stir over medium heat for 1 minute. Cool for 5 minutes. Crack the eggs into a measuring cup. Use a wooden spoon to beat the eggs into the dough, 1 at a time. Stir in the Parmesan and pepper. Spoon 18 mounds of dough onto the prepared baking sheet, spacing 2 inches apart. Bake until the profiteroles are puffed and golden, about 45 minutes. Allow the profiteroles to cool completely.
Combine the goat cheese and cream in a medium bowl. Using an electric mixer, whip together the cheese and the cream. Stir in the tomatoes, salt and pepper. Set aside.
Using a serrated knife, cut off the top of the profiteroles. Fill each profiterole with a spoonful of the goat cheese mixture and return the top of the pastry. Place a few profiteroles on a serving plate, drizzle with herb oil, and sprinkle with walnuts. Serve.
Combine the herbs in a food processor and pulse to chop the herbs. With the machine running add the oil, salt, and pepper. Transfer to a small bowl, cover with plastic wrap and set aside.