Cut each zucchini lengthwise in half, leaving any blossoms on one of the halves. With the tip of a vegetable peeler, carefully scoop out the pulp, making a little shell. Reserve the pulp.
Heat the oil in a small skillet over low heat. Add the garlic and shallot and saute one minute. Add the zucchini pulp, tomatoes, 1 tablespoon of the parsley, the thyme, and black pepper to taste. Cook stirring frequently, for 5 minutes. Cool to room temperature.
Spoon the filling into the zucchini shells. Sprinkle with the remaining parsley. Arrange on a flat basket or platter and serve at room temperature.